THE  LIBRARY 

OF 

THE  UNIVERSITY 
OF  CALIFORNIA 

PRESENTED  BY 

PROF.  CHARLES  A.  KOFOID  AND 
MRS.  PRUDENCE  W.  KOFOID 


'* 


arf  ^  ^/~*^  &~^  4*  5^ 

^  ^./fc,  ^~**±-<-^-'^'J^7 


(^ 


PHYSIOLOGY, 

GENERAL  ANATOMY, 


AND 


PATHOLOGY, 


BICHAT. 


BY  THOMAS  HENDERSON,  M.  D. 

-ss=£=- 

PROFESSOR    OF    THE    THEORT    AND    PRACTICE    OF    MEDICINE    IN    THE 


COLUMBIAN    COLLEGE,    WASHINGTON    CITT. 


PHILADELPHIA: 

CAREY,  LEA  &  CAREY— CHESNUT  STREET. 

1829. 


<n 


EASTERN  DISTRICT  OF  PENNSYLVANIA,  to  wit: 

BE  IT  REMEMBERED,  that  on  the  fourteenth  day  of  March,  in  the 
fifty-third  year  of  the  independence  of  the  United  States  of  America, 
A.  D.  1829,  Carey,  Lea  and  Carey  of  the  said  district,  have  deposited 
in  this  office  the  title  of  a  book,  the  right  whereof  they  claim  as 
Proprietors,  in  the  words  following,  to  wit: 

"  An  Epitome  of  the  Physiology,  General  Anatomy,  and  Pathology, 
of  Bichat.  By  Thomas  Henderson,  M.  D.  Professor  of  the  Theory  and 
Practice  of  Medicine  in  the  Columbian  College,  Washington  City." 

In  conformity  to  the  act  of  the  Congress  of  the  United  States,  enti- 
tuled,  "  An  act  for  the  encouragement  of  learning,  by  securing  the  co- 
pies of  maps,  charts,  and  books,  to  the  authors  and  proprietors  of 
such  copies,  during  the  times  therein  mentioned."  And  also  to  the 
act,  entitled,  "  An  act  supplementary  to  an  act,  entitled,  *  An  act  for 
the  encouragement  of  learning,  by  securing  the  copies  of  maps,  charts, 
and  books,  to  the  authors  and  proprietors  of  such  copies  during  the 
times  therein  mentioned,'  and  extending  the  benefits  thereof  to  the 
arts  of  designing,  engraving,  and  etching  historical  and  other  prints." 

D.  CALDWELL, 
Clerk  of  the  Eastern  District  of  Pennsylvania 


SKEBRBTT NINTH  STREET, 

PHILADELPHIA. 


''.Bib-jo 


TO 


I 


LATE  PROFESSOR  OF  ANATOMY  IN  RUTGERS  MEDICAL 
COLLEGE,  NEW  YORK. 

SIR, 

I  dedicate  this  little  volume  to  you,  as  a  testimony  of  my 
respect  for  you  as  a  man  of  learning,  and  especially  in  ac- 
knowledgmeht  of  your  distinguished  character  as  a  teacher  of 
anatomy. 

I  regret  that  ill  health  has  compelled  you  to  retire  from  a 
sphere  of  duty,  in  which  you  were  doing  so  much  good,  and 
acquiring  so  much  fame. 

I  consider  you  a  conspicuous  instance  of  what  genius,  in- 
dustry, and  honourable  ambition  will  accomplish;  an  example 
which  the  American  medical  student  should  ever  be  proud  to 
follow. 

Great  interest  is  felt  by  the  medical  profession  and  others 
in  the  restoration  of  your  health.     I  partake  largely  of  that 
feelingj  and  though  personally  a  stranger  to  you,  I  am  happy 
and  sincere  in  assuring  you,  of  the  great  respect  of 
Sir,  your  obedient, 

And  very  humble  servant, 

THOMAS  HENDERSON. 


Washington,  November,  1828. 


PREFATORY  REMARKS. 


THE  works  legitimately  ascribed  to  Bichat  are  volumi- 
nous and  expensive.  In  the  French  there  are  about  ten 
volumes,  in  the  translations  seven;  .and  they  are  not  al- 
ways, perhaps  not  generally,  all  found  in  private  libraries. 
These  circumstances  in  part,  induced  me  to  attempt  an 
epitome  of  the  works  of  this  great  man.  The  decisive 
motive  was  the  fact,  that  his  works  at  large  are,  from  va- 
rious causes,  toa  little  read  by  students,  before  they  com- 
mence their  public  studies,  or  before  they  graduate.  I 
allude  now  to  the  great  proportion  of  medical  students  in 
the  interior  of  the  country.  It  has  been  frequently  said 
too,  that  the  arguments  in  support  of  his  principles,  and 
the  experiments  illustrating  their  truth,  are  detailed  by 
Bichat  with  unnecessary  prolixity  and  minuteness. 

If  any  causes  tend  to  keep  from  the  medical  student  a 
familiar  acquaintance  with  the  writings  of  Bichat,  they 
should  be  removed;  if  any  thing  can  be  done  to  render 
them  more  accessible,  it  should  be  done.  I  have  thought, 
and  the  plan  has  been  approved  by  judicious  friends,  that 
such  an  attempt  as  this  volume  exhibits  might  have  these 
effects;  and  it  will  be  a  great  source  of  satisfaction  to  me, 
if  it  in  any  measure  succeeds. 

In  all  the  sciences  there  is  a  disposition  to  familiarize 
students  with  the  most  important  authors,  by  reducing 
their  works  to  the  compendious  form  of  manuals.  This 
is  done  usually,  in  the  aphoristic,  or  in  the  interro- 
gatory style.  The  last  has  been  pronounced,  if  not  the 


VI  PREFATORY    REMARKS. 

least  useful,  the  least  dignified.  I  have,  after  much  consi- 
deration, determined  to  adopt  the  form  of  question  and 
answer.  I  found  this  very  useful  and  agreeable  to  me 
when  a  student;  my  private  pupils  have  been  happily 
aided  by  it;  it  certainly  greatly  facilitates  the  private  in- 
struction of  pupils.  This  last  reason,  of  the  truth  of  which 
there  can  be  no  doubt,  would  have  been  sufficient  to  decide 
me.  It  appears  to  me  also,  that  in  submitting  the  question 
and  giving  the  answer,  the  mind  undergoes  a  double  ope- 
ration, favourably  concentrates  the  student's  attention,  and 
leads  to  a  correct  intellectual  result.  I  therefore  readily 
submit  it  to  the  student  of  this  work  to  decide,  after  he 
has  completed  the  perusal  of  it,  whether  or  not  I  have 
erred  in  adopting  the  catechetical  method.  If  this  method 
be  generally  unsystematic,  it  is  replied  that  I  give  the 
system  of  Bichat,  and  that  is  my  object.  If,  as  was  sug- 
gested by  a  medical  friend,  in  pursuing  the  course  most 
useful  to  students  I  have  sacrificed  the  dignity  of  author- 
ship, the  latter  is  most  freely  surrendered  in  order  to  ensure 
the  former. 

On  another  account  it  is  thought  this  work  may  be  well 
received.  Modern  publications  are  interposed  between 
the  medical  student  and  Bichat;  and  on  this  ground,  that 
they  omit  his  errors,  embrace  his  truths,  and  introduce 
subsequent  improvements.  There  is  some  foundation  for 
this;  but  as  to  the  supposed  erroneous  views  of  Bichat, 
may  not  "the  stone  which  the  builders  rejected"  be  yet 
found  the  sure  one  for  the  building?  And  those  views 
which  are  esteemed  improved  ones,  have  many  of  them 
yet  to  bear  the  sternness  of  critical  and  experimental  in- 
vestigation. It  is  scarcely  to  be  expected  that  a  student 
will,  after  reading  the  summaries  of  Horner,  and  of  Bayle 
and  Hollard  on  general  anatomy,  patiently  explore  the 


PREFATORY    REMARKS.  Vli 

long  and  intricate  paths  opened  in  the  elaborate  volumes 
of  Bichat.  On  the  contrary,  I  fear  these  books  may  ma- 
terially tend  to  exclude  Bichat  from  private  libraries.  If 
a  compendium  of  the  works  of  the  Father  of  general  ana- 
tomy can  be  made  to  accompany  the  recent  publications, 
I  humbly  think  it  will  conduce  to  the  student's  progress. 

I  have  read  with  unmingled  pleasure  the  General  and 
Special  Anatomy  of  Horner;  and  have  seen  with  pride 
how  favourably  it  is  noticed  abroad,  and  I  know  how  much 
good  it  is  doing  at  home.  The  volume  of  Bayle  and  Hoi- 
lard  is  an  excellent  work,  and  deserving  repeated  and  at- 
tentive perusal.  But  these  works,  although  founded  on 
the  system  of  Bichat,  should  never  supersede  his  writings. 
There  are  in  the  latter  so  many  new,  curious  and  authen- 
ticated speculations  and  facts,  not  to  be  found  in  any  pre- 
ceding or  subsequent  work,  that  they  remain  unrivalled 
in  value,  immortalizing  the  author. 

To  be  valuable,  such  a  work  as  I  have  executed,  should 
be  well  done.  Neither  time  nor  devotion  to  the  object 
have  been  spared.  It  has  been  my  endeavour  to  catch  the 
spirit  and  the  meaning  of  Bichat,  and  to  express  them 
perspicuously.  I  do  not  suppose  the  work  is  free  from 
error,  but  it  is  hoped  that  these  errors  are  neither  numer- 
ous nor  important.  I  have  depended  on  the  French  edi- 
tions for  the  correctness  of  the  book,  but  have  been  much 
aided  by  the  translations. 

Now  that  the  works  of  Bichat  are  so  valued,  it  is  but 
an  act  of  justice  to  acknowledge  the  obligations  of  the  me- 
dical student  to  those  who  have  translated  them.  It  is  due 
to  the  taste  and  talents  of  Doctor  Tobias  Watkins,  to  an- 
nounce him  as  the  first  who  engaged  in  that  undertaking. 
He  gave  a  fine  translation  of  the  work  on  Life  and  Death. 
The  treatise  on  the  membranes  was  translated  by  Doctor 


Vlll  PREFATORY    REMARKS. 

Coffin  of  Boston,  and  published  in  1813.  The  general 
anatomy  has  been  faithfully  rendered  into  our  language 
by  Doctor  Hayward,  of  Boston.  He  has  displayed  not 
less  talent  than  persevering  industry  in  laying  before  the 
profession  what  has  been  termed,  I  believe  by  Professor 
Chapman,  "a  revelation  in  medicine."  By  the  same  pen 
Beclard's  additions  have  been  translated;  and  to  Mr. 
Togno,  a  student  of  medicine,  we  are  indebted  for  the 
translation  of  the  posthumous  work  on  Pathology. 

I  have  adhered  closely  to  the  works  of  Bichat.  Scarcely 
a  remark  has  been  made  which  does  not  rest  with  him, 
for  I  neither  designed  nor  desired  to  assume  responsibility. 
The  few  observations  on  pathology  have  been  presented 
principally  to  introduce  those  truths  which  have  resulted 
from  investigations  into  general  anatomy,  or  which  are  not 
familiarly  contained  in  the  books  on  practical  medicine, 
or  the  mere  mention  of  which  is  calculated  to  lead  to  im- 
portant reflection. 

I  intended  to  preface  this  work  with  a  biographical 
sketch  of  Bichat.  I  shall  reserve  it  for  another  opportunity. 
Yet  it  may  be  appropriate  just  to  say,  that  he  was  born  in 
France  in  1771 — his  scholastic  pursuits  were  at  Lyons — 
he  there  commenced  professional  studies  under  Petit — they 
were  continued  in  Paris  under  Desault — in  1797  he  gave 
his  first  course  of  lectures — indebted  to  Pinel  for  the  first 
impulse,  he  originated  and  highly  perfected  the  science  of 
general  anatomy — he  continued  to  lecture  till  1802,  when, 
in  consequence  of  a  fall,  he  contracted  a  cephalic  form  of 
fever,  which  ended  the  life  and  labours  of  a  man,  who, 
at  the  age  of  thirty-one,  had  accomplished  works,  which 
will  be  as  lasting  as  the  science  they  have  improved. 

Six  hundred  pupils  followed  the  remains  of  their  highly 
revered  preceptor  to  the  grave. 


ams  01  tne 


AN  EPITOME, 


GENERAL  OBSERVATIONS. 

Of  the  Physiological  and  Physical  Sciences,  and  the 
Properties  which  preside  over  their  Phenomena. 

Q.  How  are  the  sciences  divided? 

t#.   Into  the  physiological  and  physical. 

Q.  What  do  you  understand  by  these  terms? 

t/?.  The  physiological  sciences  are  those  embracing  the 
philosophy  of  animate  nature.  The  physical  sciences  re- 
fer to  inanimate  nature. 

Q.  To  what  are  the  phenomena  of  animate  and  inani- 
mate nature  to  be  traced? 

A.  To  the  operation  of  vital  and  non-vital  properties. 

Q.  What  classes  of  objects  possess  vital  properties  ? 

•#.   Animals  and  vegetables. 

Q.  In  what  department  of  nature  do  you  find  the  non- 
vital  properties? 

t#.  In  the  physical  world. 

Q.  What  are  the  vital  properties? 

*ft.  Sensibility  and  contractility. 

Q.   Name  some  of  the  non-vital  properties. 

*#.   Gravity,  elasticity  and  affinity. 
2 


10  GENERAL    OBSERVATIONS. 


Characters  of  the    Vital  Properties   compared  with 
those  of  the  Physical. 

Q.  The  characteristics  of  the  vital  and  physical  pro- 
perties in  animate  and  inanimate  nature  are  strikingly 
different;  in  what  principally  consists  this  difference? 

«/?.  The  physical  are  determinate  and  invariable;  the 
vital  vary  with  every  day  and  person.  Attraction  and 
gravity  are  always  the  same;  sensibility  and  contractility 
are  ever  variant. 

Q.  Is  there  such  a  state  as  disorder  of  the  physical  pro- 
perties ? 

*#.  No.  Physiology  is  to  living  bodies,  what  astro- 
nomy, hydraulics,  &c.  are  to  inert  ones.  There  is  nothing 
in  physics  analogous  to  pathology  in  living  bodies. 

Q.  What  would  be  the  consequence  of  variableness  in 
physical  properties  ? 

Ji.  The  effect  would  be  the  disorganization  of  nature. 

Q.    Then  physical  laws  cannot  govern  living  bodies? 

«#.  No.  In  one  or  two  functions  there  is  a  combined 
action  of  vital  and  physical  properties;  such  as  the  eye 
and  ear.  The  vital  powers  always  preponderate. 

Q.  What  difference  is  observable  in  the  elementary  ar- 
rangements of  living  and  inanimate  bodies? 

Jl.  Composition  and  decomposition  are  constantly 
changing  the  elements  of  living  bodies;  but  the  elements 
of  inert  bodies  remain  the  same  until  destroyed. 

Q.  Do  animate  and  inanimate  bodies  resemble  each 
other  in  the  perpetuity  of  their  properties? 

•#.  Not  at  all.  Vital  properties  tending  to  exhaust 
themselves,  animate  bodies  but  for  a  limited  time;  they 


GENERAL    OBSERVATIONS.  11 

. 

reach  their  acme  and  decline.  Physical  laws  and  proper- 
ties exist  unimpaired  as  long  as  matter  remains. 

Q.  Are  sympathies  found  in  living  or  inert  bodies? 

«#.  Exclusively  in  the  living.  If  a  stone  be  bruised  or 
broken,  the  parts  do  not  suffer;  but  if  a  living  body  be  in- 
jured in  a  part,  the  whole  may  or  does  sympathize. 

Q.  What  are  sympathies? 

«/?.  Unnatural  vital  forces  indirectly  excited  by  remote 
impressions.* 

Q.  What  properties  belong  to  vegetable  life? 

*ft.  Organic  sensibility  and  insensible  organic  contrac- 
tility. 

Q.  What  vital  properties  do  animals  possess  beyond 
those  of  vegetables? 

t#.  Besides  organic  sensibility  and  insensible  organic 
contractility,  in  animals  you  find  animal  sensibility,  ani- 
mal contractility,  and  sensible  organic  contractility. 

Q.  What  are  the  diseases  of  vegetables? 

Jl.  They  have  not  the  nervous  affections,  nor  fevers 
which  arise  from  exalted  animal  sensibility,  and  sensible 
organic  contractility;  but  they  have  tumours,  exhalations 
and  affections  which  result  from  their  vital  properties 
above  named. 

Q.  Zoophytes  manifest  a  vital  property  beyond  those 
of  vegetables;  pray  what  is  it? 

e/?.  Sensible  organic  contractility. 

Q.  What  are  the  gradations  of  properties  assigned  by 
Bichat  to  the  three  kingdoms? 

*  Bichat  does  not  include  in  this  definition  healthy  sympathies;  these 
were  formerly  denominated  by  many  physiologists,  synergies.  The 
term  sympathy,  however,  as  at  present  employed,  comprises  both  these 
classes  of  phenomena — healthy  and  morbid  sympathies. 


12  GENERAL    OBSERVATIONS, 

•ft.  Physical  properties  to  the  mineral;  physical  pro- 
perties, organic  sensibility  and  insensible  organic  contrac- 
tility, to  the  vegetable ;  and  physical  properties  and  all  the 
organic  and  animal  vital  properties  for  theamVna/kingdom. 

Q.  What  functions  are  controlled  by  organic  sensibility 
and  insensible  organic  cpntractility? 

•ft.  Circulation,  secretion,  absorption,  nutrition,  exha- 
lation, &c. 

Q.  What  diseases  arise  from  these  properties? 

•ft.  Inflammation,  purulent  formations,  induration,  re- 
solution, haemorrhagies,  unnatural  augmentation  or  dimi- 
nution of  the  secretions,  exhalations,  increased  or  dimi- 
nished absorptions,  dropsies,  and  many  others. 

Q.  What  functions  are  governed  by  sensible  organic 
contractility? 

•ft.  Digestion,  the  circulation  in  the  large  vessels,  the 
excretion  of  urine  from  the  bladder,  &c. 

Q.  What  are  the  diseases  of  these  functions? 

•ft.  Vomitings,  diarrhoea,  irregularities  of  the  heart's 
action.  -> 

Q.   What  functions  depend  on  animal  sensibility? 

•ft.  The  external  senses,  and  what  are  termed  by  Bichat 
the  internal  senses,  as  hunger  and  thirst. 

Q.  What  diseases  arise  from  alterations  of  animal  sen- 
sibility? 

•ft.  Pain  in  its  various  forms,  itching,  smarting,  tickling, 
and  so  forth. 

Q.  In  what  is  animal  contractility  concerned? 

•ft.  In  locomotion  and  the  voice. 

Q.  What  is  the  essence  of  disease? 

•ft.  An  increase,  diminution,  modification  or  alteration 
of  some  of  the  vital  properties  just  named. 


GENERAL    OBSERVATIONS.  13 

Q.  What  does  the  treatment  of  disease  imply? 

A.  A  restoration  of  these  properties  to  a  normal  state. 

Q.  Give  an  illustration  of  this. 

.tf.  In  inflammation  your  object  should  be  to  reduce 
organic  sensibility;  in  dropsy  or  oedema  to  increase  it.  In 
convulsions  you  must  reduce  animal  contractility;  in  palsy 
increase  it. 

Q.  What  remedies  act  on  sensible  organic  contractility? 

Jl.  Emetics  and  purgatives. 

Q.  Give  examples  of  medicines  which  act  on  general 
insensible  organic  contractility* 

t/?.  Tonics,  and  acids. 

Q.  Do  any  act  on  the  insensible  organic  contractility  of 
particular  parts? 

.#.  Yes.  Nitre  in  its  action  on  the  kidneys;  mercury 
on  the  salivary  glands. 

Q.  How  do  remedies  act  in  reducing  animal  sensibility? 

«#.  By  relieving  pain  in  the  parts,  as  by  emollients;  or 
by  rendering  the  brain  insensible  by  narcotics. 

Q.  Are  medicines  necessarily  confined  in  their  opera- 
tion, to  the  reduction,  increase  or  modification  of  any  one 
of  the  vital  properties? 

Ji.  No;  they  often  operate  on  more  than  one  of  these. 

Of  the  Vital  Properties  and  their  Phenomena  consi- 
dered in  relation  to  the  Solids  and  Fluids. 

Q.  Why  is  it  not  unreasonable  to  suppose  that  the  fluids 
are  destitute  of  life? 

Ji.  Because  they  never  manifest  sensibility  and  con- 
tractility as  do  the  solids. 


14  GENERAL    OBSERVATIONS. 

Q.  What  operation  of  the  fluids  and  solids  gives  rise  to 
organic  sensibility? 

«#.  That  impression  of  the  fluids  on  the  solids,  which  is 
not  perceived  by  the  brain,  excites  organic  sensibility. 

Q.   How  does  organic  differ  from  animal  sensibility? 

«/?.  In  this,  that  animal  sensibility  is  perceived  by  the 
brain. 

Q.  What  pathological  principle  do  you  found  on  the 
location  of  the  vital  properties  in  the  solids? 

*&.  As  disease  is  but  an  alteration  of  these  forces,  and 
as  these  forces  are  found  in  the  solids,  therefore  diseases 
are  seated  primarily  in  the  solids. 

Q.  By  what  avenues  does  Bichat  suppose  the  fluids  may 
become  so  changed  as  to  cause  disease? 

»/?.  By  matters  absorbed  through  the  lacteals,  the  lungs, 
the  skin,  and  through  wounded  surfaces. 

Q.  How  does  he  divide  the  fluids? 

«#.  Into  those  destined  to  composition,  and  those  of  de- 
composition. The  first  convey  the  causes  of  disease. 

Q.  Are  sympathetic  impressions  conveyed  or  seated  in 
the  solids  or  fluids? 

«#.  Always  and  essentially  in  the  solids. 

Q.  Does  Bichat  believe  in  the  vitality  of  the  fluids? 

*#.   He  does,  but  does  not  explain  it.     The  blood  pos- 
sesses vital  properties  greater  than  those  in  the  chyle. 

Q.  What  speculation  is  founded  on  the  vitality  of  the 
fluids? 

«#.  That  it  may  influence  their  motions. 


GENERAL    OBSERVATIONS. 


15 


Of  the  Properties  Independent  of  Life.     . 

Q.  What  are  they  termed? 
A.   Properties  of  texture. 
Q.  What  are  they? 

«/?.  Extensibility  and  contractility  of  texture. 
Q.   What  do  you  mean  by  the  horny  hardening? 
«/?.  It  is  a  form  of  contractility  which  parts  undergo 
after  death,  on  exposure  to  heat,  acids,  &c. 

Q.   How  many  kinds  of  horny  hardening  are  there? 
«#.   Two;  the  sudden  and  slow.     The  first  is  produced 
by  fire  and  acids;  the  second  by  neutral  salts,  air,  alcohol, 
&c. 

Q.  What  textures  are  not  susceptible  of  the  sudden 
horny  hardening? 

«#.  The  hair,  epidermis,  and  nails. 
Q.   What  textures  are  most  susceptible  of  it? 
«#.   The  fibrous,  muscles,  tendons,  and  nerves. 
Q.  What  state  is  incompatible  with  slow  horny  hard- 
ening? 

Ji.   It  cannot  take  place  during  life,  but  the  sudden 
may,  as  you  see  in  burns. 

Q.  What  destroys  both  kinds  of  this  hardening? 
«#.   Putrefaction  of  the  texture. 
Q.  How  many  kinds  of  contractility  are  there? 
A.  Five. 

Q.  What  do  you  understand  by  animal  contractility? 
*/i.  The  influence  of  the  nerves  on  the  voluntary  mus- 
cles. 

Q.  What  is  meant  by  sensible  organic  contractility? 
»#.  The  action  of  the  involuntary  muscles  from  stimuli 


16  GENERAL    OBSERVATIONS. 

Q.   What  is  a  third  kind  of  contractility  ? 

«#.  The  contractility  of  texture  from  want  of  exten- 
sion, as  it  appears  in  the  muscles,  skin,  arteries,  veins. 

Q.  Where  is  this  contractility  of  texture  obscure? 

«#.   In  the  nerves,  bones,  and  cartilages. 

Q.  What  is  the  fourth  kind  of  contractility? 

t/?.  The  horny  hardening. 

Q.  There  is  yet  another  contractility? 

«#.  Yes,  and  a  very  important  one;  it  is  the  insen&ible 
organic  contractility,  which,  by  oscillation,  forms  the  to- 
nic forces,  or  tonicity. 

Of  Animal  Organization. 

Q.  On  what  does  the  existence  of  the  vital  properties 
depend  ? 

«/?.  On  organic  arrangement,  for  when  organization  is 
destroyed,  the  vital  properties  disappear. 

Q.  What  are  animal  bodies  composed  of? 

«/?.  An  assemblage  of  organs. 

Q.  What  are  organs  composed  of? 

Ji.   Of  several  textures. 

Q.  What  are  the  elementary  textures? 

*#.  Twenty-one  in  number;  the  cellular,  nervous  of 
animal  life,  nervous  of  organic  life,  arterial,  venous,  exha- 
lent,  absorbent,  and  glandular,  osseous,  medullary,  cartila- 
ginous, fibrous,  fibro-cartilaginous,  muscular  of  animal  life, 
muscular  of  organic  life,  mucous,  serous,  synovial,  glan- 
dular, dermoid,  epidermoid,  and  the  pilous. 

Q.   In  what  do  these  textures  differ? 

A.  They  differ  in  form;  in  their  organization;  in  their 
properties  of  life,  as  contractility  and  sensibility. 


GENERAL    OBSERVATIONS.  17 

v. 

Q.  How  are  these  organized  systems  divisible  ? 

«#.  Into  those  every  where  present  as  a  base  for  all, 
and  this  Bichat  calls  the  generative;  and  secondly,  into  the 
insulated. 

Q.  Give  examples  of  the  generative  tissues. 

*#.  The  cellular,  arterial,  venous,  exhalent,  absorbent, 
nervous. 

Q.  What  are  the  insulated  textures? 

.#.  Such  as  the  osseous,  cartilaginous,  fibrous,  mucous, 
serous,  &c. 

Q.  Is  this  distinction  absolute? 

A.  It  is  not;  but  so  far  true  as  to  be  physiologically 
important. 

Q.  Which  textures  exist  most  generally? 

.#.  The  absorbent  and  exhalent. 

Q.  Why  is  this  the  case? 

•#.  Because  nutrition  depends  on  them. 

Q.  Which  texture  is  next  in  extent? 

A.  The  cellular. 

Q.  What  tissues  are  first  developed? 

«#.  The  generative  or  general. 

Q.  What  do  you  mean  by  the  nutritive  parenchyma  of 
an  organ? 

Ji.  The  cellular,  vascular,  and  nervous  outline  of  the 
organ. 

Q.  What  is  the  nutritive  matter  of  an  organ? 

«#.  That  which  establishes  a  difference  between  the 
organs. 

Q.  Give  examples  of  this  nutritive  matter? 

A.  The  phosphate  of  lime  and  the  gelatine  of  bones  is 
one  instance;  the  fibrin  in  the  muscles  is  another. 

Q.  Where  is  this  nutritive  matter  deposited? 

3 


18  GENERAL    OBSERVATIONS. 

Ji.  In  the  nutritive  parenchyma  just  mentioned. 

Q.  What  is  the  first  aspect  of  fetal  formation? 

.ft.  It  is  a  mass  of  the  generative  tissues,  in  which  each 
organ  has  its  nutritive  parenchyma  in  form ;  and  in  which 
parenchyma  the  nutritive  matter  is  gradually  deposited, 
giving  specific  character  to  each  texture  and  organ. 

Q.  How  is  organization  enlarged? 

«/#.  First,  by  an  extension  of  nutritive  parenchyma,  and 
then  by  a  deposition  of  nutritive  matter. 

Q.  In  what  does  the  elective  power  of  an  organ  on  the 
blood  consist? 

«#.  In  the  peculiar  organic  sensibility  by  which  it 
chooses  or  rejects  appropriate  principles  of  growth  in  the 
blood. 

Q.  On  what  does  the  theory  of  secretion  exist? 

•ft.  On  the  power  of  the  peculiar  vital  forces,  and  sen- 
sibilities of  textures,  which  select  from  the  blood  that 
which  comports  with  these  forces. 

Q.  Why  does  the  body  grow  for  a  certain  period? 

«#.  It  depends  on  the  ultimate  fact  that  composition  ex- 
ceeds decomposition. 

Q.  What  is  Bichat's  theory  of  secretion? 

«#.  That  the  parenchyma  of  nutrition  is  uniform,  that 
the  nutritive,  matter  is  various,  and  that  the  parenchyma 
of  nutrition  exercises  an  eclectic  power  over  the  blood, 
selecting  materials  for  the  various  nutritive  substances. 

Q.  What  do  you  mean  by  the  life  of  a  part? 

«#.  The  properties  of  the  texture  which  compose  the 
part. 

Q.  What  do  you  understand  by  disease  of  an  organ? 

«#.  Aberration  from  the  normal  condition  of  the  vital 
forces  of  one  of  the  textures  of  an  organ. 


GENERAL    OBSERVATIONS.  19 

Q.  Is  disease  confined  at  first  to  one  texture  of  an 
organ? 

A.  Yes;  an  organ  is  seldom  attacked  at  first  in  all  its 
tissues. 

Q.  What  governs  sympathies? 

J2.  Principally  similarity  of  texture. 

Q.  Is  fever  severest  in  serous  or  mucous  disease? 

«#.  In  diseases  of  the  serous  tissues. 

Q.  How  many  sets  of  symptoms  are  there  in  inflam- 
mation? 

•ft.  Two ;  those  of  the  texture,  and  those  of  the  organ. 

Q.  What  influence  has  texture  on  the  general  pheno- 
mena of  disease? 

Ji.  It  modifies  symptoms  and  duration  of  disease. 

Q.  Be  more  explicit  in  your  answer. 

Jl.  The  different  textures  in  disease  give  different  kinds 
of  pain,  different  degrees  of  heat,  and  have  a  longer  or 
shorter  duration.  Hence  acute  and  chronic  diseases  are 
relative  to  the  vital  properties  of  the  textures;  as  for  in- 
stance, a  serous  texture  goes  through  a  disease  sooner  than 
an  osseous  tissue. 

Q.  Why  are  the  mucous,  serous,  and  glandular  tissues, 
so  much  oftener  diseased  than  others? 

Jl.  Because  their  functions  require  great  energy  in  the 
organic  sensibility  and  insensible  organic  contractility, 
and  consequently  liability  to  alterations  of  these,  or  in 
other  words  disease. 

Q.  What  is  the  correct  nosological  method? 

£.  That  of  the  diseases  which  affect  the  several  tissues. 


20  GENERAL    OBSERVATIONS. 


Of  the.  Functions. 

Q.  What  is  Bichat's  classification  of  the  functions? 

<fl.  Into  those  of  animal  life,  those  of  organic  life,  and 
the  functions  relating  to  the  species. 

Q.  What  do  you  mean  by  the  functions  of  animal  life? 

A.  Those  which  connect  us  with  external  bodies,  and 
are  peculiar  to  animals. 

Q.  What  do  you  understand  by  the  functions  of  organic 
life? 

*ft.  Those  which  serve  for  the  constant  composition 
and  decomposition  of  our  bodies  ;  these  are  possessed  by 
animals  and  vegetables ;  they  distinguish  between  organic 
and  inorganic  substances. 

Q.  What  are  the  animal  functions? 

«^.  The  senses,  voluntary  muscles,  the  larynx,  and  the 
nerves  which  are  the  agents  in  these  functions. 

Q.  What  is  the  centre  of  these? 

A.  The  BRAIN. 

Q.   Designate  the  organic  functions. 

«#.  Digestion,  circulation,  respiration,  exhalation,  ab- 
sorption, secretion,  nutrition,  calorification.  The  HEART 
is  the  centre  of  these. 

Q.  What  nerves  belong  to  these  two  sets  of  functions? 

./?.  The  cerebral  to  the  animal,  the  ganglionic  or  great 
sympathetic  to  the  organic  functions. 

Q.  What  conspicuous  distinction  should  be  drawn  be- 
tween these  two  sets  of  functions? 

A.  The  sensibility  and  contractility  peculiar  to.  them. 
There  is  the  animal  sensibility  and  animal  contracti- 
lity,  and  there  is  the  organic  sensibility,  the  sensible 


GENERAL    OBSERVATIONS.  21 

organic  contractility,  and  the  insensible  organic  con- 
tractility. 

Q.  What  was  the  ancient  opinion  as  to  proximate 
texture. 

J2.  That  the  cellular  was  the  substratum  of  all  the  solids 
of  the  body,  and  the  fibre,  the  base  of  the  cellular  was 
composed  of  gluten  and  earthy  particles. 

Q.  What  are  Beclard's  elements  of  organization? 

t/?.  Three;  viz.  the  cellular,  the  nervous,  and  muscular 
fibre. 

Q.  Are  these  very  distinct? 

A.  Yes ;  in  form,  chemical  composition,  and  vital 
functions. 

Q.  What  is  Meckel's  doctrine  of  organization? 

t/2.  That  its  elementary  substance  is  globular,  a  coagu- 
lable  matter,  and  a  union  of  these. 


OF  LIFE. 

Q.  How  do  you  define  the  term  life? 

«/?.  A  principle,  the  phenomena  of  which  are  recog- 
nized, the  nature  of  which  is  concealed;  life  is  the  aggre- 
gate of  the  functions  which  resist  death. 

Q.   How  is  life  divided? 

t/?.  Into  two  striking  modifications,  that  of  animal  life, 
and  organic  life. 

Q.  What  is  a  conspicuous  characteristic  of  organic  life? 

.#.  That  it  exists  both  in  animals  and  vegetables. 

Q.  Detail  the  peculiarities  of  animal  life? 

*ft.  It  appertains  exclusively,  to  animals.  It  is  the  life 
by  which  animated,  establishes  relations  with  all  nature. 

Q.   What  are  the  orders  in  the  functions  of  animal  life? 

t#.  The  first  is  from  the  exterior  of  the  body  to  the 
brain,  and  comprises  the  receptions,  transmission,  and  per- 
ception of  the  impression  ending  in  sensation.  The  second 
order  originates  in  the  brain,  where  volition,  arising  from 
sensation,  acts  on  the  locomotive  and  vocal  organs. 

Q.  Continue  the  analysis  of  these  two  orders  of  the 
animal  functions. 

A.  In  the  first  the  animal  is  acted  on  by  external  bo- 
dies; in  the  second  order. of  functions  the  animal  reacts  on 
these  bodies.  There  is  proportion  between  these  two  or- 
ders; a  powerful  impression  from  without  produces  a  re- 
action correspondently  great. 

Q.  What  are  the  orders  of  the  functions  of  organic  life? 

«#.  They  are  two;  first,  that  engaged  in  the  composi- 


OF    LIFE.  23 

tion;  secondly,  that  which  decomposes  the  animal:  these 
operations  are  incessant. 

Q.  What  processes  are  involved  in  the  assimilative 
functions? 

«#.  Digestion,  circulation,  respiration,  and  nutrition. 

Q.  What  processes  are  concerned  in  decomposition? 

«#.  Absorption,  circulation,  exhalation,  and  secretion 
form  the  second  order  of  the  functions  of  organic  life. 

Q.  State  the  relations  that  the  brain  and  sanguiferous 
system  bear  to  these  animal  and  organic  vital  functions. 

*#.  As  the  brain  is  a  central  system  between  external 
bodily  impressions,  and  the  reaction  of  volition  which 
follows,  so  does  the  sanguiferous  system  sustain  a  central 
position,  in  organic  life,  between  assimilation  and  decom- 
position. 

Difference  between  Animal  and  Organic  Life. 

Q.  What  is  the  essential  distinction  in  the  organs  of  ani- 
mal and  organic  life? 

«/?.  In  those  of  animal  life  there  is  symmetry;  in  organic 
life  there  is  the  utmost  irregularity. 

Q.  Give  examples  of  these  two  properties. 

A.  The  double  organs  of  vision,  of  hearing,  the  hemi- 
spheres of  the  brain,  the  double  sets  of  nerves,  are  in- 
stances of  the  symmetry  of  the  organs  of  animal  life.  The 
liver,  the  heart,  the  spleen,  the  intestines  are  always  sin- 
gle and  often  very  irregularly  disposed.  There  is  irregu- 
larity in  the  number  of  lobes  composing  the  right  and  left 
lungs:  the  divisions  of  the  pulmonary  artery  are  unlike 
each  other  in  several  respects.  These  are  a  few  of  the  ex- 
amples of  the  irregularity  in  the  conformation  of  the  or- 
gans of  organic  life. 


24  OF    LIFE. 

Q.   Why  are  the  animal  functions  double? 

•ft.  A  perpetuation  of  their  existence  being  essential, 
the  loss  of  one  is  supplied  by  the  duplicate. 

Q.  The  animal  and  organic  functions  differ  in  another 
respect,  what  is  it? 

«/?.  In  the  animal  there  is  harmonious  function  as  well 
as  symmetrical  structure;  in  the  organic  there  is  nothing 
of  that.  This  harmony  in  the  animal  functions  is  essen- 
tial to  concordant  sensation. 

Q.  Give  further  illustration  of  this  idea  of  harmony  in 
function. 

«#.  If  the  two  auditory  or  optic  nerves  conveyed  dif- 
ferent impressions,  the  sensations  and  actions  must  conse- 
quently be  confused.  Discordant  action  of  the  hemispheres 
of  the  brain,  must  produce  similar  discrepancy. 

Q.  But  this  general  principle  of  harmony  in  function 
does  not  hold  good  in  the  action  of  the  right  and  left  sides 
of  the  body. 

*ft.  It  does  not;  but  the  superiority  of  the  right  arm  and 
hand  is  the  effect  of  habit. 

Q.  Of  what  consequence  is  irregularity  in  organic  life? 

«#.  You  will  infer  its  unimportance  from  the  fact,  that 
one  kidney  may  separate  more  urine  than  the  other;  that 
one  lung  may  admit  more  venous  or  eject  more  arterial 
blood  than  the  other;  that  more  organic  action  may  exist 
in  one  salivary  gland  than  another;  that  one  side  of  the 
spleen,  pancreas,  or  liver  may  receive  more  blood  than 
another,  and  yet  the  organic  action  maintain  its  integrity 
and  regularity. 

Q.  You  have  already  given  some  of  the  distinctions  be- 
tween animal  and  organic  life;  there  are  others,  and  will 
you  state  one? 


OF    LIFE.  25 

.#.  An  important  one  is,  that  animal  life  is  intermittent 
in  its  functional  actions,  whereas  organic  life  is  perpetually 
active  from  birth  to  death. 

Q.  Can  you  exemplify  the  preceding  answer? 

A.  The  functions  of  the  brain  are  suspended  in  sleep, 
but  those  of  the  heart  continue.  Muscular  action  is  ex- 
hausted by  fatigue,  but  secretion,  absorption,  and  exhala- 
tion continue  uninterruptedly. 

Q.  What  does  a  complete  intermission  of  the  action  of 
animal  life  denote? 

*ft.  It  denotes  perfect  sleep.  This  sleep  is  more  or  less 
complete,  as  the  functions  of  animal  life  are  one  or  all  in- 
volved in  this  intermission ;  particularly  as  the  senses  shall, 
one  or  all,  have  intermitted  their  connexion  with  external 
objects. 

Q.  How  do  you  account  for  dreaming? 

Ji.  It  is  the  escape  of  one  part  of  animal  life  from  the 
torpidness  which  pervades  the  rest. 

Q.  There  is  yet  another  respect  in  which  the  animal 
and  organic  functions  differ,  what  is  it? 

A.  Impressions  on  animal  life  are  ever  variant,  and  they 
lose  their  effect  from  habit;  whereas  organic  life  is  regu- 
larly under  the  impression  of  uniform  and  accustomed  sti- 
muli, which  do  not  lose  their  power  from  habitual  action. 

Q.  Where  are  the  intellectual  faculties  and  the  passions 
located? 

A.  The  intellect  appertains  to  animal  life,  the  passions 
originate  in  organic  life. 

Q.  How  is  it  that  organic  life  is  the  seat  of  the  pas- 
sions, if  these  result  from  perception  and  impression  on 
the  brain? 

1 


" 


26  OP    LIFE. 

*#.  The  nerves  and  brain  serve  merely  as  conductors 
to  the  impressions  which  excite  passions  by  irritating  or- 
ganic life.  The  brain  arrests  the  impressions  that  excite 
intellect,  but  it  conducts  the  passions  to  organic  life. 

Q.  Will  you  name  some  of  the  effects  of  the  passions 
on  our  organs? 

•fl.  Anger  hurries  the  action  of  the  heart;  joy  does  so  to 
some  extent:  terror  enfeebles  the  energy  of  the  heart,  so 
that  blood  is  not  sent  to  the  capillaries.  These  passions  act 
so  intensely  on  the  source  of  the  circulation,  as  sometimes 
to  stop  the  action  of  the  heart,  producing  syncope.  Sor- 
row affects  the  respiratory  organs.  The  passions  variously 
influence  the  stomach,  spleen,  intestines,  liver,  and  even 
the  blood-vessels,  so  as  to  occasion  lesions  in  them.  Ex- 
halation, absorption,  nutrition  are  less  influenced  by  the 
passions.  Now,  observe,  that  under  all  these  alterations 
of  organic  life  by  the  passions,  the  animal  functions  are 
unhurt. 

Q.  But  if  organic  life  is  the  seat  and  source  of  the  pas- 
sions, how  is  it  that  these  passions  so  excite  the  organs  of 
animal  life? 

«/?.  As  some  of  the  passions  increase  the  heart's  action, 
it  follows  that  an  increased  volume  of  blood  is  sent  to  the 
brain;  thus  the  centre  of  animal  life  is  excited,  and  the 
functions  dependent  on  it  are  exalted.  So  likewise  in  those 
passions  which  enfeeble  the  heart's  action,  the  impetus  of 
blood  being  lessened,  the  functions  of  animal  life  are,  by 
the  diminished  energy  of  its  centre,  debilitated. 

Q.  Is  there  a  common  epigastric  centre  for  the  passions? 

A.  There  is  not.  The  impulse  of  passion  arises  in  dif- 
ferent persons,  under  different  circumstances,  from  differ- 
tnt  passions,  involving  different  abdominal  organs. 


OP    LIFE.  27 

Q.  Is  the  term  sympathetic  nerve,  as  it  is  commonly 
used,  a  correct  one? 

«#.  It  is  not.  The  ganglions  give  rise  to  what  is  called 
the  sympathetic  nerve,  not  the  nerve  to  the  ganglions. 

OP  THE  PROPERTIES  OP  ANIMATED  BEINGS. 

Q.   How  are  these  properties  divided? 

«#.  Into  the  properties  of  life,  and  those  of  texture. 

1.   Vital  Properties. 

Q.  What  are  these? 

*ft.  Sensibility  and  contractility. 

Q.  How  is  sensibility  divided? 

•#.  Into  animal  and  organic  sensibility. 

Q.  What  is  the  great  distinction  between  organic  and 
animal  sensibility? 

«#.  In  the  first,  the  organ  exhibits  the  faculty  of  re- 
ceiving an  impression,  without  transmitting  it  to  a  com- 
mon centre^  animal  sensibility  implies  not  only  the  re- 
ception of  an  organic  impression,  but  the  transmission  of 
that  impression  to  a  common  centre,  and  that  centre  is  the 
brain.  This  transmission  and  cerebral  impression  consti- 
tute the  difference  between  organic  and  animal  sensibility. 

Q.  What  phenomena  are  supported  by  organic  sensi- 
bility? 

•/?.  Digestion,  circulation,  secretion,  exhalation,  absorp- 
tion, nutrition,  and  others.  This  sensibility  is  common 
to  the  plant,  the  zoophyte,  and  the  most  perfect  animal. 

Q.  What  phenomena  depend  on  animal  sensibility? 

Jl.   Sensation,  perception,  volition,  intellect,  pleasure, 


2S  OF    LIFE, 

pain.     Now,  this  sensibility  is  not  the  attribute  of  vege- 
tables. 

Q.  In  what  respects  do  organic  and  animal  sensibility 
resemble  each  other? 

Ji.  They  originate  from  the  same  principle,  viz.  that 
of  life;  and  they  vary  only  in  degree  of  exaltation.  Hence 
organic  sensibility  can,  by  irritation,  be  exalted  into  ani- 
mal sensibility. 

Q.   Does  organic  sensibility  vary  in  its  nature? 

Jl.  It  does  not ;  it  varies  in  force.  In  disease  it  is  in- 
creased or  diminished.  In  health,  each  organ  has  its  pri- 
mitive determinate  quantum  of  sensibility,  which  places 
it  in  relation  to  its  appropriate  stimulus,  as  the  -urine  to 
the  bladder,  the  air  to  the  lungs.  The  organs  in  health 
will  admit  no  other  than  their  appropriate  stimuli. 

Q.   Can  you  illustrate  this  more  clearly? 

»#.  In  the  healthy  state,  serous  exhalants  carry  serum 
only,  but  let  their  organic  sensibility  be  exalted  into  ani- 
mal by  irritation,  and  you  will  see  them  allowing  the  pas- 
sage of  blood.  This  change  is  often  independent  of  the 
healthy  calibre  of  the  vessels;  for  a  vessel  large  enough  in 
health  to  convey  a  red  globule,  will,  from  its  organic  sen- 
sibility, be  in  relation  only  to  white  fluids. 

Q.  What  effect  has  sudden  death  on  these  two  kinds  of 

sensibility? 

•/?.   It  annihilates  immediately  the  animal,  but  more 

slowly  the  organic  sensibility. 

Q.   How  is  contractility  divided  and  subdivided? 

•/?.  It  is  divided  into  animal  and  organic  contractility. 
The  last  is  subdivided  into  sensible  and  insensible  organic 
contractility. 

Q.   What  do  you  understand  by  the  term  contractility? 


OF    LIFE.  29 

*fl.  It  is  spontaneous  motility,  (motilit6,J  an  inherent 
faculty  of  living  bodies. 

Q.  What  features  serve  to  distinguish  the  two  kinds  of 
contractility  from  each  other? 

«#.  Animal  contractility  has  its  impulse  from  the  brain, 
submits  to  the  influence  of  the  will,  ceases  when  the  com- 
munication of  the  organ  with  the  brain  is  cut  off,  has  its 
seat  in  what  are  called  the  voluntary  muscles,  and  pre- 
sides over  locomotion  and  the  voice. 

Q.  Place  organic  contractility  in  contrast  with  the  ani- 
mal. 

«/?.  It  has  no  common  centre,  such  as  the  brain  is  to  ani- 
mal contractility;  it  is  uncontrolled  by  the  will;  finds  its 
principle  in  each  contracting  or  moving  organ;  and  pre- 
sides over  the  digestive,  secretory,  absorbent,  exhaling, 
and  nutritive  phenomena. 

Q.  What  effects  have  sudden  death  and  disease  on  these 
contractilities? 

«#.  This  death  suddenly  destroys  animal  contractility, 
the  organic  remaining  larger  in  existence.  The  effects  of 
disease  may  be  seen  in  paralysis,  where  animal  contracti- 
lity is  lost,  while  the  organic  remains. 

Q.  What  connexion  have  these  contractilities  with  their 
respective  sensibilities? 

A.  They  arise  from  them,  depend  on  them,  inasmuch 
as  action  is  the  result  of  sensation. 

Q.  Is  there  not  a  difference  in  the  relation  of  the  two 
to  their  respective  sensibilities? 

&.  There  is;  for  the  excitement  of  animal  sensibility 
does  not  necessarily  induce  animal  contractility.  For  in- 
stance, an  impression  made  on  a  limb  or  set  of  muscles, 
does  not  necessarily  induce  the  motion  of  that  member 


30  OP    LIFE. 

or  of  those  muscles.  But  organic  contractility  always  fol- 
lows the  excitement  of  organic  sensibility;  this  is  exem- 
plified in  the  action  of  the  heart  from  the  stimulus  of  the 
blood. 

Q.  How  do  you  explain  this  difference  in  the  con- 
nexion of  the  two  sensibilities  and  contractilities? 

«#.  In  animal  life  there  is  an  intermediate  power,  the 
brain,  which  may,  or  may  not,  at  pleasure,  follow  animal 
sensibility  with  corresponding  contractility :  we  speak  now 
of  the  normal  state  of  these  parts.  In  organic  life,  there 
is  no  such  intermediate,  controlling  power;  for  the  stimu- 
lus to  the  organic  sensibility,  the  blood  for  instance,  im- 
mediately acts  on  the  contractility  of  the  heart,  and  ex- 
cites it  to  action. 

Q.  Repeat  the  division  of  organic  contractility. 

«/?.  Its  forms  are  sensible  organic  and  insensible  organic 
contractility. 

Q.  Can  you  give  examples  of  sensible  organic  contrac- 
tility? 

*/?.  You  perceive  it  in  the  motion  of  the  heart,  in  the 
contractions  of  the  stomach,  especially  in  the  act  of  vomit- 
ing ;  it  is  likewise  sensible  in  the  intestines. 

Q.  What  will  exemplify  insensible  organic  contrac- 
tility? 

*&.  The  power  by  which  the  excretory  vessels  act  on 
their  respective  fluids,  that  by  which  the  secretory  organs 
act  on  the  blood  which  finds  access  into  them,  that  which 
the  lymphatics  exercise  on  the  substances  exposed  to  their 
extremities ;  these  are  all  by  virtue  of  insensible  organic 
contractility. 

Q.  How  does  sensible  organic  contractility  differ  from 
animal  contractility? 


OF    LIFE.  31 

J3..  Sensible  organic  contractility  is  involuntary,  animal 
contractility  in  its  ordinary  condition  involves  volition. 

Q.  Be  more  particular  in  distinguishing  sensible  and  in- 
sensible organic  contractility  from  each  other. 

Ji.  Uterine  contraction,  the  heart's  action,  and  vomit- 
ing, are  instances  of  sensible  organic  contractility;  they 
can  be  felt.  The  action  of  the  biliary  vessels,  indeed 
of  the  capillaries  generally,  are  examples  of  insensible 
organic  contractility;  they  cannot  be  felt.  Yet  organic 
contractility,  whether  sensible  or  insensible,  is  the  same 
principle  in  different  degrees  of  exaltation.  The  fact  that 
insensible  organic  contractility  is  without  the  sphere  of 
volition  distinguishes  it  from  animal  contractility. 

Q.  There  yet  remains  a  difference  between  organic  con- 
tractility and  organic  sensibility,  yet  to  be  stated;  it  is 
singular  and  important,  what  is  it? 

•ft.  You  have  seen  that  a  mere  exaltation  of  organic  sen- 
sibility from  disease,  will  convert  it  into  animal  sensibility 
or  pain ;  now  organic  contractility,  sensible  or  insensible, 
cannot  be  converted  or  exalted  to  animal  contractility. 

Q.  Should  contractility  be  considered  as  exclusively 
attached  to  the  muscular  tissue  ? 

«#.  It  should  not — it  is  a  property  of  all  the  tissues  to 
a  greater  or  less  extent. 

Q.  What  do  the  two  forms  of  organic  contractility  re- 
present? 

«#.  The  sensible  organic  contractility  is  the  irritability, 
and  the  insensible  organic  contractility  is  the  tonicity  of 
writers. 


32  OP    LIFE. 


2.  Properties  of  Texture. 

Q.  What  are  these? 

Jl.  They  are  extensibility  and  contractility  of  tissue. 

Q.  Can  you  offer  some  examples  of  extensibility  of 
texture? 

*#.  The  walls  of  the  abdomen  extended  by  tumours, 
serous  infiltrations,  or  pregnancy ;  the  extension  of  the 
tunica  vaginalis  in  dropsy;  that  of  a  part  filled  with  ab- 
scess. All  this  is  extensibility  of  texture,  a  property  in- 
dependent of  life. 

Q.  On  what  do  these  textural  properties  depend? 

«#.  They  depend  on  the  arrangement  of  the  organic 
fibres  of  parts;  where  these  fibres  are  loose,  there  is  much 
extensibility,  as  in  the  muscles,  and  vice  versa. 

Q.   What  organs  are  most  extensible? 

Jt.  The  muscles,  skin,  and  cellular  tissue;  those  least 
vso,  are  the  bones,  cartilages,  tendons,  nails,  &c. 

Q.  How  can  you  exemplify  contractility  of  texture? 

«#.  After  distending  causes  have  been  removed,  you 
see  parts  return  to  their  natural  state.  It  is  exhibited  in 
the  contraction  of  the  abdominal  parietes  after  delivery, 
or  on  the  evacuation  of  peritoneal  dropsy.  It  appears 
again  when  the  stomach  or  bowels,  after  great  distention 
with  wind,  resume  their  wonted  dimensions. 

Q.  Is  this  contractility  of  texture  greater  in  the  dead  or 
living  parts? 

*#.  Although  these  properties  of  texture  arc  indepen- 
dent of  life,  yet  this  imparts  to  them  additional  force. 

Q.  Present  an  example  of  a  part  possessing  all  the  va- 
rious forms  of  contractility. 


OP    LIFE.  33 

%/?.  A  muscle  will  exemplify  this  best.  Thus,  1st,  cere- 
bral impulse  conveyed  through  the  nerves,  occasions  a  con- 
tractility; this  is  animal  contractility,  and  involuntary; 
2d,  on  the  application  of  a  strong  stimulant,  there  will  be 
a  muscular  motion,  which  is  sensible  organic  contracti- 
lity, or  irritability;  this  is  involuntary;  3dly,  a  penetra- 
tion of  all  the  parts  of  the  muscle  by  its  nutritive  fluids, 
developes  a  movement  of  oscillation,  which  is  insensible 
organic  contractility  or  tonicity,  and  this  is  involuntary; 
4thly,  cut  across  a  muscle  and  its  fibres  retract;  this  is  the 
contractility  of  texture;  lastly,  various  organs  possess 
one  or  more  of  these  forms  of  contractility. 

Q.  What  form  of  contractility  is  possessed  by  all  living 
parts? 

•ft.   Insensible  organic  contractility  or  tonicity. 

Q.  Name  that  contractility  which  is  the  attribute  of 
all  parts,  living  or  dead? 

A.  All  tissues,  whether  living  or  dead,  possess  contrac- 
tility of  texture. 

Q.  Can  you  give  a  tabular  recapitulation  of.  the  pro- 
perties of  living  bodies? 

«#.  The  general  division  is  into  vital  and  textural  pro- 
perties. 

Vital  Properties. 

A.  Sensibility — the  faculty  which  an  organ  feels. 

a.  *ftnimal  sensibility ;  in  which  the  sensation  is  felt 
by  the  organ,  and  conveyed  to  the  brain. 

b.  Organic  sensibility ;  in  which  the  organ  feels,  but 
the  sensation  is  not  conveyed  to  the  brain. 

B.  Contractility — the  faculty  by  which  motion  volun- 
tary or  involuntary  takes  place. 

a.  Animal  contractility — voluntary. 
5 


34  OF    LIFE, 

b.   Organic  contractility — involuntary. 
Organic  contractility  is  divided  into — 

1.  Sensible  organic  contractility;  as  the  motion  of 
the  heart,  contractions  of  the  stomach,  &c.—  these 
are  sensible,  but  involuntary. 

2.  Insensible  organic  contractility ;  as  capillary  action 
or  motion:  this  is  insensible,  and  involuntary. 

Properties  of  Texture. 

A.  Extensibility. 

B.  Contractility. 

Q.  What  composes  the  life  of  the  organs? 

«#.  A  modification  of  the  above  mentioned  vital  proper- 
ties, which  control  the  circulation  and  temperature  of  each 
organ. 

OF  ANIMAL  LIFE. 

Q.  What  is  the  first  conspicuous  distinction  between 
animal  and  organic  life? 

*#.  The  period  of  the  commencement  of  the  two  lives. 
Organic  life  commences  with  the  rudiment  of  foetal  life 5 
animal  life  begins  after  birth. 

Q.  Why  do  you  say  that  animal  life  is  quiescent  before 
birth? 

«/!?.  None  of  the  senses  being  in  exercise,  the  foetus  does 
not  feel;  there  is  neither  sensation,  perception,  nor  voli- 
tion. It  is  not  probable  that  the  liquor  amnii  causes  any 
sensation. 

Q.  Is  it  true  that  the  surrounding  temperature,  and  the 
liquor  amnii,  are  the  only  external  objects  capable  of  ex- 
citing sensation  in  the  foetus? 

t#.  The  contact  of  the  uterus  may  be  admitted  as  a  fee- 


OP    LIFE.  35 

ble  cause.  From  all  that  has  been  ascertained  it  may  be 
inferred  that  the  senses  are  not  in  action  in  the  foetus,  espe- 
cially the  touch. 

Q.  One  attribute  of  animal  life  certainly  exists  in  the 
foetus,  if  the  senses  do  not,  what  is  it? 

•#.  Locomotion  does  truly  exist,  but  that  of  the  foetus, 
is  not  the  consequence  of  external  sensation  or  of  animal 
life.  It  results  from  the  brain  being  sympathetically  stimu- 
lated, by  the  organs  of  organic  life,  in  their  foetal  deve- 
lopement.  The  locomotion  exists,  it  is  involuntary.  For 
example,  the  foetal  heart  sends  undue  measure  of  blood  to 
the  brain ;  it  is  thereby  excited,  and  thus  involuntary  mus- 
cular action  is  induced.  Now  compare  this  with  voluntary 
locomotion  in  independent  life,  in  which  sensation,  per- 
ception, and  volition  concur. 

Q.  There  is  another  feature  distinguishing  animal  from 
organic  life,  what  is  it? 

«#.  The  operations  of  organic  life  are  perfect  at  birth ; 
those  of  animal  life  become  so  only  in  process  of  education 
and  habitual  exercise.  The  senses  of  the  infant  trace,  at 
first,  confused  general  images;  so  do  the  perceptions;  the 
intellectual  operations  are  latest  in  attaining  perfection. 

Q.  What  are  the  laws  governing  this  education  of  the 
functions  of  animal  life? 

*ft.  Let  it  suffice  to  state  one.  The  improvement  or 
perfection  of  any  one  of  these  is  at  the  expense  of  others; 
tha£  of  the  memory  at  the  cost  of  judgment,  &c.  The  per- 
fection of  one  sense  is  at  the  expense  of  another.  Now  it 
is  curious,  that  the  operations,  not  the  education,  of  or- 
ganic life  are  under  the  influence  of  a  gimilar  law:  the  ex- 
cessive action  of  one  organ  is  at  the  expense  of  another. 


3G  OF    LIFE, 

OF  ORGANIC  LIFE. 

Q.  What  organ  in  this  system  is  first  developed? 

t#.   The  heart,  the  punctum  saliens. 

Q.  What  is  the  difference  between  foetal  organic  and 
independent  organic  life? 

.#.  The  difference  is  great  as  to  the  number  of  func- 
tions in  operation.  For  instance,  in  the  foetus  there  is 
little  assimilation,  because  the  blood  comes  prepared  from 
the  mother;  there  is  neither  digestion  nor  respiration; 
there  is  no  excretion.  In  after  life  all  these  functions  are 
in  play.  In  foetal  organic  life  there  is  rapid  assimilation, 
but  slow  and  slight  decomposition. 

Q.  On  what  does  the  perfect  operation  of  organic  life 
depend? 

ttf.  Not  on  education,  nor  on  habit,  nor  on  symmetri- 
cal arrangement  as  in  animal  life,  but  on  original  structure 
or  organization. 

Q.  Where  is  the  moral  character  seated  ? 

Jl.  The  passions  constituting  this,  are  seated  in  organic 
life! 

Q.  In  natural  death,  which  life,  animal  or  organic,  dies  first? 

A.  Animal  life  does.  The  senses  give  way;  the  skin 
becomes  tough,  and  hard,  and  being  deprived  of  much  of 
its  vascularity,  it  is  the  seat  of  obscure  touch.  As  sensa- 
tion is  blunted,  the  mental  faculties  decline;  that  declen- 
sion weakens  volition;  the  voluntary  muscles  are  disused; 
thus  the  organs  of  animal  life  die  in  detail.  Organic  life 
fails  in  the  same  gradual  manner;  digestion,  secretion  and 
absorption  decline  pr  cease;  the  capillary  circulation  from 
the  loss  of  tonicity  is  embarrassed;  the  general  circulation 
ceases,  and  the  heart  ultimately  dies.  Such  is  the  natural 
death  of  the.  old  man. 


ON  DEATH. 

Q.  Is  the  dependence  of  animal  life  on  organic,  or  that 
of  organic  life  on  animal,  greatest? 

t/?.  Intimately  as  they  are  related,  it  is  to  be  observed, 
that  death  of  the  animal  organs,  instantly  follows  that  of 
the  organic;  whereas  organic  life  continues  some  time 
after  animal  life  has  ceased. 

Q.  What  is  the  sure  indication  of  complete  death? 

•ft.  The  termination  of  the  functions  or  phenomena  of 
organic  life. 

Q.  What  triple  alliance  is  necessary  to  life? 

*fl.  The  functions  of  the  heart,  lungs  and  brain. 

On  the  Influence  of  the  Death  of  the  Heart  upon  that 
of  the  Brain. 

Q.  How  does  the  heart  influence  the  brain? 

«/2.  Through  the  circulation  of  the  blood,  and  by  ner- 
vous transmissions. 

Q.  How  does  the  circulation  of  red  blood  influence  the 
brain? 

«#.  In  two  ways:  by  the  motion  of  the  blood  in  the  ar- 
teries; and  by  the  intrinsic  qualities  of  red  blood,  vivify- 
ing they  may  be  called.  Too  great  motion  of  the  brain 
from  the  heart's  action,  or  too  little  will  morbidly  excite 
or  debilitate  the  cephalic  functions. 

Q.  In  injection  of  air  into  the  veins,  where  is  its  fatal 
impression  made? 


38  ON   DEATH. 

.#.  On  the  brain,  for  the  heart  continues  to  live  after 
animal  life  is  destroyed. 

On  the  Influence  of  the  Death  of  the  Heart  upon  that 
of  the  Lungs. 

Q.  What  constitutes  the  functions  of  the  lungs? 

«/?.  Two  processes;  first,  the  mechanical  one  of  expan- 
sion by  the  aid  of  the  muscles,  and  the  chemical  one  of 
changing  the  black  blood  to  red. 

Q.  In  cases  where  the  heart  with  black  blood  ceases  to 
operate,  how  are  the  lungs  interrupted? 

«#.  There  is  no  blood  in  the  lungs  in  this  case;  the  brain 
is  indirectly  affected,  because  the  heart,  receiving  no  red 
blood  from  the  lungs,  sends  none  to  the  brain.  Without 
this  red  blood  the  brain  is  unable  to  maintain  the  action  of 
the  ribs  and  intercostal  s,  so  the  mechanical  function  of  the 
lung  ceases. 

Q.  How  are  the  lungs  affected,  when  the  red  blood 
heart,  is  interrupted  in  its  functions? 

«#.  The  operation  is  an  indirect  one  through  the  brain; 
thus,  the  brain  receives  no  red  blood,  consequently  it 
communicates  no  power  to  the  intercostals  and  diaphragm; 
and  the  lungs  cease  to  live  in  consequence  of  a  suspension 
of  their  mechanical  functions. 

On  the  Influence  of  the  Death  of  the  Heart  upon  that 
of  the  Organs  generally. 

Q.  How  is  the  death  of  the  organs  generally,  induced  by 
that  of  the  heart  with  red  blood? 

.#.   The  organs  of  animal  life  die,  because  the  heart  sends 


ON    DEATH.  39 

no  red  blood  to  the  brain.  The  organs  of  organic  life  cease, 
because  the  arterial  movement  is  extinct,  and  because  they 
have  not  the  excitement  of  red  blood. 

Q.  Explain  this  motion  or  arterial  impulse  which  you 
say  is  so  important? 

*ft.  Habitual  movement  is  alike  essential  to  animal  as 
well  as  organic  life;  without  it  they  all  languish.  You 
see  muscular  motion;  the  motion  given  to  the  brain  by  the 
pulsation  of  the  arteries;  the  movement  of  the  thoracic 
viscera  in  respiration  and  that  of  the  heart;  and  in  the 
abdominal  organs  there  is  the  pulsation  of  the  arteries,  the 
capillary  and  oscillatory  motions,  the  contractions  and 
dilatations  of  the  stomach  and  bowels.  You  observe  how 
conspicuous  a  share  in  the  general  motion,  arterial  impulse 
has;  now  in  the  death  of  the  red  blood  heart,  it  is  extinct. 

Q.  Has  not  the  death  of  the  red  blood  heart,  an  indirect 
effect  in  inducing  general  death? 

«tf.   Yes — it  does  so  through  the  medium  of  the  brain. 

Q.  Is  there  any  relation  between  the  quantity  of  blood 
conveyed  to  a  part  and  the  vital  forces  of  that  part? 

*ft.  A  very  important  one;  the  vital  forces  are  exalted 
or  diminished  as  the  quantity  of  blood  sent  to  an  organ  is 
increased  or  diminished. 

On  the  Influence,  of  the  Death  of  the  Heart  on  General 
Death. 

Q.  Can  you  trace  the  influence  of  the  death  of  the  heart 
in  the  production  of  general  death? 

JL.  The  death  of  the  heart  arrests  the  impulse  of  blood 
on  the  brain,  and  thus  animal  life  is  first  extinguished. 
This  influence  on  the  brain  is  of  two  kinds;  first,  the  mo- 


40  ON    DEATH. 

tion  given  io  the  brain  by  arterial  action;  secondly,  the 
vivifying  power  of  red  blood.  The  cessation  of  the  same 
impulses  on  organic  life  induces  death  in  that  system,  in 
which  organic  sensibility  and  insensible  organic  contrac- 
tility are  last  to  die.  Death  in  the  heart  then  is  felt,  first 
in  the  death  of  the  animal,  and  secondly  in  that  of  the  or- 
ganic system  of  life. 

Q.  Why  do  the  vital  forces  continue  longer  in  organic 
than  animal  life? 

*#.  Animal  life  having  but  one  common  centre,  the 
brain,  the  death  of  that  is  followed  simultaneously  by  that, 
of  all  its  dependencies.  In  organic  life  there  being  many 
ganglionic  centres,  life  is  there  kept  up  longer. 

Q.  Where  does  death  from  mental  emotion  first  take 
place? 

«#.  It  takes  place  first  in  the  heart. 
Q.  What  organ  is  primarily  affected  in  syncope? 
Ji.   The  heart  always. 

Q.  What  reasons  do  you  assign  for  this  theory  of  syn- 
cope? 

«/?.  The  passions  affect  organic  life  primarily,  and  not 
animal  life;  the  phenomena  of  syncope  are  the  same 
whether  produced  by  the  passions,  by  cardiac  obstructions, 
or  by  haemorrhage ;  in  the  approach  of  syncope  the  sensa- 
tion is  first  felt  in  the  heart;  the  heart  is  diseased  by  the 
passions,  while  the  brain  is  not;  the  heart  has  direct  in- 
fluence over  the  brain,  white  cerebral  influence  on  the 
heart  is  indirect,  for  the  heart  continues  to  live  some 
time  after  the  brain  dies,  whereas  the  brain  dies  instant- 
ly on  the  death  of  the  heart;  lastly,  palpitations  and  other 
impressions  on  the  heart  proceed  from  the  same  causes 
which  induce  syncope. 


ON    DEATH.  41 

Q.  There  is  a  great  difference  in  the  mode  by  which 
asphyxia,  syncope,  and  apoplexy  induce  death,  what  is  it? 

Jj.  In  asphyxia  death  commences  in  the  lungs,  in  syrt- 
cope  in  the  heart,  in  apoplexy  in  the  brain. 

On  the  Influence  of  Death  of  the  Lungs  upon  that  of 
the  Heart. 

Q.  In  diseases,  where  does  death  usually  commence? 

t/?.   In  the  lungs. 

Q.   In  syncope,  what  is  the  condition  of  the  lungs? 

«#.  They  are  empty  and  collapsed,  because  the  heart 
failing  suddenly,  blood  is  not  thrown  into  them. 

Q.  Repeat  the  mode  in  which  death  takes  place  in  the 
lungs? 

*ft.  By  the  cessation  of  its  mechanical  and  chemical 
functions. 

Q.  What  causes  affect  the  mechanical  functions  of  the 
lungs? 

t#.  A  wound  which  exposes  the  lungs  in  both  cavities; 
such  a  section  of  the  spinal  marrow  as  cuts  off  the  inter- 
costal and  phrenic  nerves  from  cerebral  influence;  the  sud- 
den introduction  of  a  large  quantity  of  fluid  into  the  cavities 
of  the  thorax,  &c. 

Q.  How  are  the  chemical  functions  of  the  lungs  de- 
stroyed? 

•#.  By  asphyxia,  strangulation,  submersion,  or  a  vacuum 
however  produced. 

Q.  How  does  an  interruption  to  the  mechanical  func- 
tions of  the  lungs  affect  the  heart  ? 

«#.  The  collapse  of  the  lungs  mechanically  obstructs 
the  circulation  of  the  blood  from  the  right  side  of  the 

6 


42  f  ON    DEATH.         f  ^ 

heart;  and  the  lungs  do  not  transmit  red  blood  to  the 
heart. 

Q.  How  does  a  cessation  of  the  chemical  function  of 
the  lungs  affect  the  heart? 

•ft.  It  is  by  the  operation  of  black  blood  on  the  vital 
forces  of  the  heart.  Understand,  it  is  not  contact  of  black 
blood  with  the  lining  membrane  of  the  heart,  but  because 
black  blood  conveyed  to  the  heart  through  the  coronary 
arteries  fails  to  maintain  its  vital  forces. 

Q.  How  does  black  blood  destroy  life  in  the  organs  ge- 
nerally ? 

•ft.  By  its  contact  with  the  minute  fibres,  &c.  of  the  or- 
gans, and  not  by  impression  made  on  the  internal  surface 
of  the  heart. 

Q.  Is  this  operation  of  black  blood-on  the  minute  fibres, 
or  on  the  nerves  which  supply  them  ? 

•ft.   It  rnay  be  on  the  nerves. 

Q.  Why  does  the  left  side  of  the  heart  always  die  first? 

.#.' Because  its  supply ,  of  blood  fails  soonest;  for  as 
death  progresses  the  blood  accumulates  in  the  right  side  of 
the  heart,  keeping  it  alive  longest. 

Q.  Why  are  the  right  heart  and  the  veins  always  more 
loaded  with  blood  in  asphyxia,  than  the  red  blood  heart 
and  arteries? 

•ft.  Three  causes  concur  to  produce  this;  viz.  the  kind 
of  blood  in  circulation,  the  state  of  the  lungs,  and  that  of 
the  heart. 

Q.  What  agency  has  the  blood  in  inducing  this  loaded 
state  of  the  right  side  of  the  heart  and  of  the  veins? 

•ft.  In  asphyxia  the  heart  circulates  black  blood;  this 
being  unfit  for  secretions,  exhalations  and  nutrition,  is  not 
consumed  for  the  purposes  of  the  oeconomy,  it  therefore 


ON    DEATH.  43 

passes  directly  to  the  veins  from  the  arteries  and  fills 
them. 

Q.  Did  you  not  say  that  the  lungs  contributed  to  this 
fulness  of  the  right  heart  and  veins  in  asphyxia? 

•tf.  The  passage  of  blood  from  the  right  heart  to  the 
lungs,  is  impeded  by  the  weakness  of  their  chemical  func- 
tion; this  weakness  arising  from  the  circulation  of  black 
blood,  in  the  bronchial  arteries  in  asphyxia.  This  state  of 
the  lungs,  stagnates  blood  in  the  right  or  black  blood  side 
of  the  heart. 

Q.  The  third  cause  for  this  collection  of  blood  in  the 
right  heart  and  veins  was  the  condition  of  the  heart  itself, 
explain  this? 

«/2.  The  powers  of  the  right  auricle  and  ventricle  are 
debilitated  by  the  collection  of  blood  in  them  from  the 
two  causes  above  assigned;  this  debility  still  further  fa- 
vours the  congestion  in  the  large  veins  near  the  heart. 

Q.  Why  does  the  vascular  system  with  red  blood,  con- 
tain so  little  of  that  fluid  in  asphyxia? 

JL.  Because  the  obstruction  in  the  lungs  prevents  the 
flow  of  blood  to  the  aortic  side  of  the  heart,  and  because 
the  arteries  empty  themselves  by  their  inherent  powers, 
into  the  veins. 

Q.  How  is  the  lividity  of  parts  in  asphyxia  to  be  ac- 
counted for? 

JJ.  It  has  been  attributed  to  reflected  venous  blood;  it 
is,  however,  owing  to  the  fact  that  in  asphyxia  the  heart 
circulates  black  blood. 


44  ON    DEATH. 


On  the  Influence,  of  the  Death  of  the  Lungs  upon  that 
of  the  Brain. 

Q.  How  does  death  of  the  lungs  influence  that  of  the 
brain  in  asphyxia? 

w2.  In  the  death  of  the  lungs  the  failure  of  their  chemi- 
cal functions  sends  black  blood  to  the  heart;  the  heart 
sending  it  to  the  brain,  the  latter  penetrated  by  black 
blood,  dies. 

Q.  Some  curious  experiments  confirm  this  deleterious 
action  of  black  blood  on  the  brain,  what  are  they? 

*#.  Arterial  blood  from  the  carotid  of  one  dog,  was 
thrown  into  the  carotid  of  another  dog  which  had  a  liga- 
ture next  to  the  heart;  the  animal  lived.  Venous  or  black 
blood  was  then  used  in  the  experiment,  and  the  dog  was 
killed  at  once.  The  black  blood  did  not  excite  the  brain, 
or  was  poisonous  to  it. 

Q.  Is  not  the  death  in  the  case  above  stated  owing  to 
the  want  of  pulsation  or  arterial  motion  in  the  brain  ? 

A.  It  is  not;  because,  in  the  process  of  asphyxia  in 
animals,  the  aorta. pulsates  black  blood  into  the  brain;  in 
this  then,  there  was  no  want  of  cerebral  motion  from  the 
blood. 

Q.   On  what  part  does  asphyxia  first  produce  death? 

*ft.  On  the  brain ;  animal  life  first  suffers.  Those  who 
have  escaped  suffocation  complain  of  drowsiness,  a  general 
numbness,  head-ache,  paralysis,  even  convulsion,  all  evi- 
dently seated  in  the  brain. 


ON    DEATH.  15 

On  the  Influence  of  the  Death  of  the  Lungs  upon  that 
of  the  Organs  generally. 

Q.  How  do  you  ascertain  the  progress  of  asphyxia  in 
animals? 

«#.  Tie  the  trachea  high  up;  make  an  opening  below 
the  ligature,  introduce  a  tube  with  a  cock  to  it.  By  this 
means  you  can  admit  air  as  you  please  to  the  lungs.  Adapt- 
a  small  tube  and  cock  to  the  crural  artery,  and  by  this  you 
ascertain  the  state  of  the  blood  in  the  progress  of  the 
asphyxia. 

Q.  If  the  cock  of  the  pipe  be  shut  immediately  after 
inspiration,  what  changes  are  made  in  the  blood?  ^ 

«/2.  In  thirty  seconds  the  blood  begins  to  darken;  in  a 
minute  its  colour  is  deepened;  in  two  minutes  it  is  black 
blood. 

Q.  What  is  the  effect  of  stopping  the  cock  after  a  strong 
expiration? 

«/?.  The  blood  becomes  sooner  black. 

Q.  What  takes  place  when  you  pump  the  air  from  the 
lungs  with  a  syringe? 

«#.  The  blood  blackens  immediately;  the  crural  artery 
throws  a  black  stream,  as  soon  as  the  red  blood  which  it 
contained  can  be  emptied. 

Q.  And  what  if  the  air  cells  are  completely  filled  be- 
fore the  cock  is  stopped  ? 

«#.  The  blood  is  slower  in  becoming  black. 
Q.  After  asphyxia  has  been  established  for  some  mi- 
nutes, if  the  stop  be  opened,  what  takes  place? 

«#.  A  strong  expiration  first  takes  place;  then  several 
deep  rapid  respirations,  and  an  instantaneous,  not  gradual 
restoration  of  the  blood  to  a  red  colour.  These  changes 


46  ON    DEATH. 

are  more  or  less  complete  according  to  the  quantity  of 
air  admitted. 

Q.  From  the  rapidity  with  which  the  blood  is  reddened, 
what  do  you  suppose  to  be  the  course  of  the  colouring 
principle? 

A.  There  can  be  little  doubt  that  the  colouring  matter 
passes  the  membranes  of  the  air  cells  to  the  blood,  and  not 
through  the  absorbents. 

Q.  When  asphyxia  is  removed  by  the  introduction  of 
air,  how  is  the  heart  affected  ? 

•fl.  Red  blood  is  sent  to  the  left  heart,  it  penetrates  the 
coronary  arteries,  and  reanimates  the  forces  of  the  heart, 
which  were  exhausted  by  the  black  blood. 

Q.  If  the  heart's  action  is  once  entirely  checked,  can  it 
be  restored  by  the  injection  of  air  into  the  lungs? 

ifl.  It  cannot.  The  heart  having  ceased  to  beat,  the 
coronary  arteries  no  longer  nourish  the  vital  forces  of  the 
heart  with  blood.  A  temporary  syncope  may  be  removed. 

Q.  What  are  the  symptoms  in  asphyxia  from  hydrogen 
and  carbonic  acid  gas? 

«/?.  After  a  hurried,  agitated,  embarrassed  respiration 
for  a  few  minutes,  the  blood  becomes  black. 

Q.  Why  is  the  blood  longer  in  blackening  when  these 
gases  are  respired? 

«#.  The  expelled  and  reabsorbed  air  in  this  process,  af- 
fords all  its  vivifying  principles  to  the  blood.  But  when 
the  tube  and  cock  are  simply  shut,  there  is  not  this  agita- 
tion of  the  respirable  air  remaining  in  the  lungs. 

Q.  If  oxygen  be  respired,  what  occurs? 

«#.  The  blood  is  much  longer  in  losing  its  red  colour.' 

Q.  How  do  you  prove  that  black  blood  is  circulated  in 
the  organs  in  asphyxia? 


ON    DEATH. 


*#.  By  the  fact,  that  the  left  heart  does  act  for  some  time 
after  black  blood  is  thrown  into  it;  which  of  itself  proves 
that  it  must  throw  black  blood  into  the  organs. 

Q.  Is  there  not  other  evidence  of  the  injection  of  the 
organs  with  black  blood  in  asphyxia? 

Jl.  Dissection  has  given  beautiful  evidence  of  it  in  the 
muscles.  In  them  you  see  the  black  drops  of  blood  oozing 
from  the  vessels  of  the  cut  muscle,  while  the  colouring 
matter  of  the  muscular  fibre  preserves  them  red.  Again, 
this  black  blood  is  seen  in  the  arteries  of  the  nerves.  It 
is  stagnant  in  the  skin,  because  the  black  blood  does  not 
sufficiently  excite  the  capillary  circulation  to  action.  The 
passage  of  black  blood  into  the  mucous  and  serous  mem- 
branes is  clearly  evidenced  by  exposing  these  tissues, 
and  shutting  the  stop-cock  in  the  trachea. 

Q.  What  phenomena  are  accounted  for  by  the  left  heart 
circulating  black  blood? 

A.  Besides  explaining  many  other  pathological  facts, 
it  accounts  for  the  existence  of  black  blood  in  the  arteries 
after  death;  it  likewise  explains  the  darkness  of  the  mu- 
cous membranes  after  death. 

Q.  What  effect  has  the  black  blood  on  the  tissues  ? 

«#.  Defective  in  exciting  power,  the  vital  forces  of  the 
organs  penetrated  by  black  blood  diminish;  this  is  from  a 
destruction  of  their  own  vital  forces  that  the  organs  suffer, 
not  from  direct  dependence  on  the  heart  or  brain.  The 
destruction  of  organic  life  is  an  independent  process,  as 
that  of  animal  life,  connected  as  the  two  may  be. 

Q.  What  effect  has  asphyxia  on  the  white  organs,  or 
those  to  which  no  blood  is  ordinarily  sent? 

*ft.  The  question  cannot  be  answered. 


48  ON    DEATH. 


On  the  Influence  of  Death  of  the  Brain  on  general 
Death. 

Q.  Will  you  state  precisely  the  order  in  which  death 
progresses,  when  the  mechanical  function  of  the  lungs  is 
interrupted? 

t/?.  First,  the  mechanical  phenomena,  then  the  chemical 
fail  from  want  of  air;  next  the  cerebral  action  from  want  of 
red  blood  excitement;  then  animal  life,  sensation,  locomo- 
tion, and  the  voice,  from  the  loss  of  cerebral  action  and 
red  blood ;  then  the  general  circulation ;  next  the  capillary 
circulation,  from  the  want  of  action  excited  by  red  blood 
in  secretion,  absorption,  exhalation;  lastly,  digestion  fails. 
This  is  the  order  of  death  on  loss  of  the  mechanical  func- 
tion of  the  lungs. ' 

Q.  Now  give  the  order  in  which  death  supervenes  when 
the  chemical  function  of  the  lungs  ceases? 

«#.  1st,  Interruption  of  the  chemical  phenomena;  2d, 
Necessary  subsequent  suspension  of  cerebral  action;  3d, 
Cessation  of  sensation,  of  voluntary  locomotion,  of  the 
voice,  and  mechanical  phenomena  of  respiration ;  4th,  An- 
nihilation of  the  heart's  action,  and  of  the  general  circula- 
tion; 5th,  Termination  of  the  capillary  circulation,  of  the 
secretions,  of  exhalation,  absorption,  and  consequently  of 
digestion;  6th,  Cessation  of  animal  heat,  which  is  the  re- 
sult of  all  the  functions.  This  is  the  progress  of  death, 
when  the  chemical  functions  of  the  lungs  cease. 

Q.  How  do  asphyxiae  vary? 

A.  The  process  is  slow  or  rapid;  the  subject  is  convuls- 
ed or  calm. 

Q.  What  gases  produce  asphyxia  most,  speedily? 


ON    DEATH.  ,  49 

*#.  Sulphuretted  hydrogen,  nitrous  gas,  effluviae  from 
privies  produce  it  more  speedily  than  other  gases,  or  than 
a  vacuum  does. 

Q.  How  do  you  divide  asphyxise?, 

*#.  Into  those  produced  by  want  of  air,  and  those  from 
poisonous  gases.  In  the  first,  death  is  produced  by  the 
circulation  of  black  blood  purely;  in  the  second  there  is 
added  to.  the  black  blood  a  deleterious  substance.  In  some 
cases  death  is  produced  by  the  poisonous  effluvise  alone. 

Q.  There  are  two  modes  by  which  deleterious  gases  af- 
fect the  lungs,  what  are  they  ? 

*#.  They  affect  the  nerves  of  the  lungs,  and  these  react 
by  sympathy  on  the  brain;  and  they  pass  into  the  blood, 
and  thus  likewise  exert  a  morbid  influence  on  the  brain 
and  organs  in  general.  Simple  contact  of  a  deleterious  gas 
with  a  mucous  surface  does  not  produce  death  immediately. 

Q.  Is  it  certain  that  air  will  pass  through  the  membrane 
lining  the  bronchiae,  into  the  blood-vessels? 

«/?.  It  is  rendered  certain  by  direct  and  analogical  proof. 
Experiments  on  animals  show  that  a  quantity  of  air  en- 
ters the  blood-vessels,  and  may  be  drawn  off  with  the 
blood.  Hydrogen  has  been  drawn  from  the  arteries,  almost 
as  pure  as  when  forced  into  the  blood. 

Q.  On  what  system,  do  the  deleterious  vapours  absorb- 
ed into  the  general  circulation,  in  asphyxia,  operate  ? 

J3.  On  the  brain  and  nerves.  The  reasons  for  this  opi- 
nion are,  that  the  symptoms  are  stupor  and  convulsions; 
that  the  symptoms  are  the  same  when  the  gases  are  in- 
haled, as  when  injected  into  the  brain;  the  phenomena,  on 
restoration  from  this  absorption,  are  cephalic,  such  as  tre- 
mors, pain  in  the  head,  &c.  These  all  point  to  the  brain 
as  the  system  on  which  these  deleterious  poisons  operate. 

7    i 


50  ON    DEATH. 

The  contact  of  black  blood  with  the  organs  has  doubtless 
some  agency  in  inducing  death. 

Q.   In  diseases  where  does  death  begin? 

«/?.   In  the  lungs. 

Q.  What  is  the  colour  of  the  arterial  blood  after  death 
from  disease? 

Jl.  It  is  black,  because  death  commencing  in  the  lungs, 
their  chemical  functions  give  way,  the  blood  sent  to  the 
left  heart  is  black,  and  consequently  the  arterial  blood  is 
so  too. 

Q.  When  death  begins  in  the  heart,  what  is  the  colour 
of  the  arterial  blood? 

€#.   It  is  red,  and  the  lungs  are  empty. 

Q.  When  death  commences  in  the  brain,  what  is  the 
condition  of  the  lungs? 

»#.   Generally  they  are  empty  of  blood. 

On  the  Influence  of  Death  of  the  Brain  upon  that  of 
the  Lungs. 

Q.  Does  death  of  the  brain  affect  the  lungs  directly  or 
indirectly? 

«#.  From  experiments  made  in  cutting  the  sympathetic 
nerve  and  par  vagum,  it  is  presumed  that  direct  cerebral 
influence  does  not  induce  death  of  the  lungs.  For  although 
all  these  nerves  be  cut,  respiration  continues  for  some  time; 
yet  surely  if  direct  cerebral  influence  operates  on  the  lungs 
it  is  by  these  nerves. 

Q.  How  then  does  death  of  the  brain  induce  that  of  the 
lungs? 

•#.  Indirectly,  by  cutting  off  the  cerebral  influence,  pa- 
ralysing the  diaphragm  and  intercostal  muscles,  and  thus 
destroying  the  mechanical  functions  of  the  lungs. 


ON    DEATH.  51 

Q.  What  view  then  shall  we  take  of  respiration? 

Jl.  Respiration  is  a  common  function,  serving  as  a  point 
of  contact  between  the  animal  and  organic  lives,  attached 
to  the  first  by  its  mechanical,  and  to  the  second  by  its  che- 
mical functions. 

On  the  Influence,  of  Death  of  the  Brain  upon  that  of 
the  Heart. 

Q.  Is  the  heart  directly  influenced  by  the  death  of  the 
brain  ? 

A.  The  direct  influence  of  the  brain  is  extended  only 
to  the  voluntary  organs;  the  heart  not  being  an  organ  of 
volition,  we  conclude  it  is  not  under  direct  cerebral  influ- 
ence. Experiments  prove  the  absence  of  this  direct  in- 
fluence. 

Q.  By  what  intermediate  organ  does  death  of  the  brain 
act  on  the  heart? 

A.  Through  the  lungs.  There  is  interruption  of  the 
cerebral  action;  then  annihilation  of  the  action  of  muscles 
of  animal  life,  consequently  a  cessation  of  the  mechanical 
functions  of  the  lungs ;  next,  suspension  of  the  chemical 
functions,  penetration  by  black  blood  of  the  fibres  of  the 
heart,  and  its  death?  * 

Q.  Why  is  the  blood  red  or  black  in  different  surgical 
operations? 

«/#.  This  depends  on  the  embarrassment  of  the  pulmo- 
nary function;  when  that  is  very  great  the  chemical  func- 
tions of  the  lungs  cease,  and  the  blood  discharged  is  black. 


52  ON    DEATH. 


On  the  Influence  of  Death,  of  the  Brain  on  the  organs 
generally. 

Q.  How  does  the  death  of  the  brain  affect  that  of  all 
the  organs? 

t#.  The  organs  of  animal  life  die  directly,  because  of 
their  immediate  dependence  on  the  brain. 

Q.  But  is  not  the  influence  on  organic  life  equally  direct? 

•#.  Evidently  not;  the  phenomena  of  disease,  and  ex- 
periment, prove  it.  These  experiments  show  that  the  brain 
exercises  only  indirect  influence  on  organic  life.  The  death 
of  the  brain  destroying  the  mechanical  function  of  the 
lungs,  the  chemical  functions  also  cease,  causing  thereby 
the  penetration  of  organic  parts  with  black  blood;  this 
overwhelms  them,  and  they  die. 

On  the  Influence  of  Death  of  the  Brain  on  general 
Death. 

Q.  State  distinctly  the  successive  phenomena  produced 
on  the  body  in  general  by  death  of  the  brain. 

«#.  There  is  death  of  the  brain,  of  animal  life;  cessation 
of  the  mechanical  functions  of  the  lungs;  cessation  of 
the  chemical  functions  of  the  lungs;  black  blood  in  the 
arteries;  death  of  the  heart;  death  of  organic  life;  cessa- 
tion of  the  capillary  circulation;  destruction  of  animal  heat, 
as  well  as  that  of  the  life  of  the  white  organs. 


OF  THE  CELLULAR  SYSTEM. 

Q.   Give  a  definition  of  the  cellular  tissue. 

•ft.  It  is  composed  of  an  assemblage  of  filaments,  and 
soft,  whitish  laminae  interwoven  and  intersecting  each 
other  in  various  ways,  with  very  irregular  communicating 
spaces,  forming  reservoirs  for  the  fatty  and  serous  fluids. 

Q.  What  relations  does  this  texture  bear  to  the  several 
organs? 

t/?.  It  surrounds,  separates,  and  connects  them;  and 
continuing  to  their  interior  structure,  it  enters  universally 
into  their  composition. 

Q.  Define  more  particularly  the  relations  of  this  tex- 
ture to  the  exterior  of  the  various  organs. 

*fl.  There  are  organs  which  have  one  surface  free,  the 
other  adherent;  the  cellular  texture  is  connected  only  with 
the  adherent  side  of  these  organs.  There  are  other  parts 
entirely  surrounded  by  neighbouring  organs;  the  cellular 
textuue  entirely  surrounds  these. 

Q.  Which  are  the  organs  with  a  free  and  an  adherent 
surface? 

*#.  The  skin,  the  serous  and  mucous  membranes. 

Of  the  Sub-cutaneous  Cellular  Texture. 

Q.  At  what  part  is  the  cellular  texture  most  adherent 
to  the  skin? 

«#.  At  what  is  termed  the  median  line  of  the  body; 
viz.  the  middle  of  the  nose,  lips,  sternum,  and  linea  alba 


54  OF    THE    CELLULAR    SYSTEM. 

Q.  -Where  is  this  sub-cutaneous  texture  most  dense? 

*#.  On  the  scalp;  on  the  palmar  and  plantar  surfaces, 
and  at  the  annular  ligaments. 

Q.  Why  is  this  texture  loose,  as  in  the  face  and  on  the 
abdomen,  and  dense  elsewhere? 

•#.  To  favour  the  functions  of  parts,  where  looseness 
avails  some,  and  density  others. 

Q.  How  does  the  density  of  cellular  structure  affect 
dropsical  and  emphysematous  swellings? 

*#.  Where  it  is  dense,  there  is  neither  a  collection  of 
water  nor  air. 

Q.  When  is  this  density  of  cellular  structure  at  the  an- 
nular ligaments  most  observable? 

*#.   In  infants,  and  in  very  fat  persons. 

Q.  What  are  the  uses  of  the  sub-cutaneous  cellular  tex- 
ture? 

.#.  It  allows  mobility  to  the  skin,  facility  to  the  mo- 
tions of  subjacent  parts,  and  it  serves  to  defend  from  cold. 
It  is  more  abundant  in  winter  than  in  summer,  and  it  is 
found  in  greater  quantity  in  animals  inhabiting  cold  cli- 
mates. Recollect  the  chilliness  which  accompanies  atte- 
nuation in  chronic  diseases. 

Q.  In  what  part  of  the  cellular  texture  does  serum  most 
readily  accumulate? 

*ft.  In  the  sub-cutaneous  portion,  and  in  this,  because  of 
its  laxity. 

Of  the  Sub-mucous  Cellular  Texture. 

Q.  What  is  the  great  difference  between  the  sub-mucous 
and  the  sub-cutaneous  cellular  textures? 

Jl.  The  sub-mucous  is  much  more  dense  in  its  whole 
expansion. 


OP    THE    CELLULAR    SYSTEM.  55 

Q.  What  would  be  the  consequence  of  a  loose  sub-mu- 
cous cellular  texture? 

*ft.  Dropsy  would  form  in  a  loose  texture,  and  the  hol- 
low organs  be  closed  by  their  sides  being  pressed  into 
contact. 

Q.  What  exempts  the  sub-mucous  cellular  texture  from 
emphysema? 

Jl.  The  density  of  its  structure,  which  prevents  gaseous 
distention. 

Q.  Why  is  the  sub-cutaneous  cellular  tissue  more  liable 
to  phlegmon  than  the  sub-mucous? 

«#.  Perhaps,  because  of  its  laxity  of  structure,  and  of 
its  freer  exposure  to  the  causes  of  phlegmonous  inflamma- 
tion. 

Q.  There  is  yet  another  important  result  from  the  den- 
sity of  the  structure  of  the  sub-mucous  cellular  coat? 

•/?.  It  fits  it  for  giving  origin  and  insertion  to  the  mus- 
cular fibres  of  the  hollow  organs,  such  as  the  stomach, 
bowels,  and  bladder. 

Of  the  Sub-serous  Cellular  Texture. 

Q.  Is  this  texture  generally  loose  or  dense? 

»#.  Remarkably  loose;  it  is  liable  to  serous  and  emphy- 
sematous  distention. 

Q.  Why  is  it  thus  loose? 

*fl.  For  adaptation  to  the  dilatations  and  contractions  in 
the  serous  membranes. 

Q.  Can  you  give  some  examples  of  dense,  adherent, 
serous  texture? 

«#.  The  two  layers  of  the  pericardium — the  adhesion 
of  the  arachnoides  to  the  dura  mater"  are  instances. 


00  OF    THE    CELLULAR    SYSTEM. 

Q.  What  does  this  intimate  union  of  the  serous  and 
fibrous  membranes  constitute? 

A.  They  form  what  are  called  the  sero-fibrous  mem- 
branes. 

Of  the  Arterial  Cellular  Texture. 

Q.  What  are  the  peculiarities  of  this  texture? 

&.  It  is  remarkably  dense;  it  is  never  infiltrated  with 
serum;  fat  does  not  accumulate  in  it;  it  is  rarely  found  in 
a  state  of  inflammation. 

Q.  How  is  this  arterial  texture  formed? 

•#.  It  is  formed  by  a  gradual  condensation  of  the  neigh- 
bouring cellular  texture. 

Q.  Are  the  arterial  fibres  implanted  in  this  dense  coat, 
as  the  muscular  fibres  of  the  stomach,  &c.  are  in  the  sub- 
mucous  cellular  tissue? 

*#.  No;  the  arterial  cellular  tunic  adheres  too  loosely 
to  the  vessels  to  admit  that  supposition. 

Of  the  Venous  Cellular  Texture. 

Q.  What  characterizes  this  texture? 

A.  It  is  not  so  dense  as  the  arterial,  and  is  more  dry. 
It  is  not  liable  to  fatty  or  serous  infiltrations. 

Q  How  is  the  cellular  cylinder  of  the  veins,  and  arte- 
ries to  be  distinguished  from  the  nervous  filaments  and 
branches? 

.#.  The  cellular  texture  is  white ;  the  nerves  are  gray ; 
this  is  ascertained  by  deliberate  maceration. 

Q.  What  other  canals  have  a  cellular  cylinder? 

«#.  The  excretory  ducts,  those  of  the  pancreas,  gall- 


OP    THE    CELLULAR    SYSTEM.  57 

bladder,  &c.  If  the  absorbents  did  not,  by  their  fine- 
ness, preclude  demonstration,  it  would  doubtless  be 
found  that  they  have  a  cellular  coat,  as  well  as  the  blood- 
vessels. 

Of  the  Cellular  Texture  embracing  the  Organs  on  all 
•tSides. 

Q.  What  organs  are  included  here? 

•ft.  All  except  those  already  mentioned. 

Q.  What  are  the  effects  of  this  cellular  investment? 

•ft.  It  insulates  the  several  organs ;  it  insulates  likewise 
their  vitality ;  it  forms  a  line  of  separation  between  them. 
It  sometimes  prevents  the  extension  of  disease  from  one 
organ  to  a  contiguous  one;  as  when  the  peritoneum  is  in- 
flamed without  the  viscera  being  affected,  or  as  when  the 
sub-cutaneous  organs  are  healthy,  while  the  skin  is  in 
eruption. 

Q.  Is  this  the  only  barrier  to  the  extension  of  disease  in 

these  circumstances? 

• 

*fl.  No;  the  difference  in  the  vital  forces  of  different, 
though  contiguous  organs,  also  prevents  the  extension  of 
disease. 

Q.  But  does  this  cellular  investment  always  perform 
the  salutary  office  of  arresting  the  spreading  of  diseased  ac- 
tion? 

•ft..  It  does  not;  for  by  taking  on  disease,  it  facilitates 
its  extension. 

Q.   Can  you  illustrate  the  preceding  answer? 

i#.  The  extension  of  tumours,  that  of  phlegmon,  and 
that  of  rheumatism  swelling  a  joint,  are  examples. 

8 


58  OP    THE    CELLULAR    SYSTEM. 

Q.  Is  there  no  other  influence  spread  by  this  cellular 
atmosphere  around  the  organs? 

t/#.   Medicinal  agency  is  conveyed  by  it. 

Q.   Give  instances  of  this. 

•ft.  The  effect  of  blisters,  cataplasms,  and  other  appli- 
cations may  be  adduced. 

Q.  How  are  the  vital  forces  of  organs  generally  in- 
jured? 

Ji.  In  three  ways:  1st,  by  direct  irritation;  2d,  by 
sympathy;  3d,  by  cellular  communication.  The  last  is 
exemplified  in  the  discolouration  and  inflammation  of  the 
skin  over  a  carious  bone. 

Q.  What  other  physiological  office  is  performed  by  this 
cellular  investment? 

t/2    It  facilitates  the  motion  and  expansion  of  organs. 

Q.  What  other  means  have  some  organs  to  facilitate 
their  mobility? 

Ji.  The  serous  membranes  perform  this  office  in  many 
cases. 

• 
Of  the.  Internal  Cellular  Structure  of  the  Organs. 

Q.  What  relation  does  this  bear  to  the  several  organs? 

»#.  It  enters  intimately  into  their  elementary  structure; 
it  surrounds  each  vessel,  nerve  and  fibre;  it  insulates  each 
by  sheathing  it;  and  it  favours  the  mobility  of  the  fibres 
and  vessels  of  the  organs. 

Q.   Does  it  partake  of  the  vital  properties  of  the  organs? 

Ji.  It  does  not;  the  cellular  texture  has  its  own  vital 
properties.  It  has  not  the  sensibility  of  the  nerve  into  the 
structure  of  which  it  enters;  it  has  not  the  contractility  of 
the  muscle,  nor  yet  the  secretion  of  the  gland. 


OF    THE    CELLULAR    SYSTEM.  59 

Q.  Are  its  diseases,  distinct  from  those  of  the  organs 
into  which  it  enters? 

*#.  They  are.  Tumours  form  in  this  cellular  texture 
within  the  organ,  or  suppuration  occurs  in  it;  while,  as 
you  will  conspicuously  see  in  tumour  or  abscess  of  the 
liver,  the  secretion  of  bile  will  go  on.  The  function  of  the 
lungs  going  on,  in  the  course  of  extensive  disease  in  them, 
is  another  illustration  of  this  principle. 

Q.  How  is  this  cellular  texture  discovered  in  some  or- 
gans? 

*#.   Maceration  and  ebullition  will  exhibit  it. 

Q.  What  proves  its  existence  in  bones  and  cartilages? 

•ft.  The  granulations  essentially  of  a  cellular  nature, 
which  sprout  from  these  in  their  diseases  and  injuries. 

Q.  Is  there  any  organ  destitute  of  this  internal  cellular 
texture? 

«#.  No — it  is  an  essential  constituent  of  the  nutritive 
parenchyma  of  every  organ. 

Cellular  Texture  of  the  Head. 

Q.  Where  do  you  find,  on  the  head,  this  texture  most 
abundant? 

*ft.   In  the  face;  on  the  cranium  there  is  little. 

Q.  Is  there  much  in  the  interior  of  the  cranium  ? 

A.  Very  little;  a  small  quantity  is  found  where  the  ves- 
sels go  in  and  out. 

Q.  To  what  is  the  redness  of  the  eye  in  phrenitis 
ascribed? 

«#.   To  the  cellular  communication  through  the  orbit. 

Q.  What  occasions  the  weight  and  pain  in  the  head  in 
coryza? 


60  OF    THE    CELLULAR    SYSTEM. 

t#.  The  cellular  communication  through  the  cribriform 
plate  of  the  ethmoid  bone,  favours  the  extension  of  the 
pain  in  the  head. 

Q.  To  what  does  Bichat  ascribe  the  coup  de  soleil? 

•/?.  To  the  cellular  connexion  between  the  external  and 
internal  membranes  of  the  cranium  through  the  sutures!!! 

Q.  Why  in  erysipelas  of  the  scalp  do  you  see  the  pus 
and  serum  in  the  eyelids  ? 

Ji.  Because  of  the  communications  of  the  cellular  tex- 
ture of  the  cranium  with  that  of  the  face. 

Of  the  Cellular  Texture  of  the  Trunk  and  Extremities. 

Q.  Where  is  the  spinal  or  vertebral  cellular  texture 
principally  found? 

•#.  There  is  little  found  along  the  spine  externally; 
there  is  much  on  the  anterior  surface  of  the  vertebral  co- 
lumn. There  is  very  little  in  the  cavity  of  the  vertebral 
canal. 

Q.  Where  do  depositions  from  the  course  of  the  spine 
sometimes  show  themselves? 

«/2.   In  the  groin,  from  cellular  communications. 

Q.  Where  is  the  cervical  cellular  texture  most  abun- 
dant? 

Ji.  In  the  lateral  parts,  where  the  lymphatic  glands  are. 
It  abounds  also  about  the  neck  generally. 

Q.  What  evidence  is  there  of  the  communication  of  the 
cervical  and  pectoral  cellular  textures? 

A.  The  extension  of  emphysema  from  the  lungs  to  the 
neck. 

Q.  Where  is  the  pectoral  cellular  texture  principally 
found? 


OP    THE    CELLULAR    SYSTEM.  61 

Ji.  In  the  interval  formed  by  the  fold  of  the  mediastf- 
num,  about  the  pericardium,  and  where  the  large  vessels 
come  out. 

Q.  How  does  this  pectoral  texture  communicate  with 
the  abdominal  ? 

•fl.  Through  the  diaphragmatic  openings. 

Q.   Where  do  you  meet  with  external  pectoral  texture? 

*ft.  In  great  quantities  in  the  breasts  of  women  and  men, 
and  under  the  pectoral  muscles. 

Q.  Why  has  disease  of  the  peritoneum  more  influence 
on  the  right  pleura  than  the  left? 

*ft.  The  peritoneum  on  the  right  side  being  kept  fixed  by 
the  convex  surface  of  the  liver,  the  communications  of 
the  abdominal  and  pectoral  cellular  textures  are  there 
more  constant  and  operative,  than  where  the  peritoneum, 
towards  the  left  pleura,  is  loose  and  floating  with  the 
viscera. 

Q.  With  what  has  the  pectoral  cellular  texture  peculiar 
relation  ? 

<fl.  With  the  cellular  texture  of  the  superior  extremities. 

Q.  Where  is  the  abdominal  cellular  texture  most  abun- 
dant? 

Ji.  Where  the  large  vessels  enter  the  viscera,  and  about 
the  kidneys. 

Q.  What  are  the  principal  relations  and  communica- 
tions of  the  abdominal  cellular  texture? 

«#.  They  are  with  the  genital  organs  and  inferior  extre- 
mities through  the  abdominal  ring  and  crural  arch.  The 
abdominal  cellular  texture  bears  the  relation  to  that  of  the 
lower  extremities,  which  the  pectoral  does  to  that  of  the 
superior. 

Q.  Is  the  cellular  texture  abundant  in  the  pelvis? 


62  OF    THE    CELLULAR    SYSTEM. 

»/?.  Very  much  so,  in  order  to  protect  the  distending 
viscera  of  that  cavity. 

Q.  Where  is  the  cellular  texture  of  the  superior  and 
inferior  extremities  principally  found? 

*#.  Around  the  scapulo-humeral,  and  the  ilio-femoral 
articulations. 

Q.  What  physiological  reason  is  there  for  the  diminish- 
ing quantity  of  cellular  texture  towards  the  extremities? 

••/?.  That  the  positive  operations  of  the  hands  and  feet 
might  not  be  encumbered  by  it. 

Q.  What  is  particularly  interesting  in  the  cellular  tex- 
ture of  the  different  cavities? 

A.  The  communications  through  the  several  openings 
above  mentioned,  through  which  inflammation,  and  serous 
and  other  infiltrations  are  extended. 

Q.  On  what  does  corpulency  depend  ? 

«#.  On  a  preternatural  distention  of  the  cells  of  this  tex- 
ture. 

Q.  Are  these  cells  increased  in  size  as  they  are  full  or 
empty  ? 

«#.  They  enlarge  to  accommodate  the  fat  and  serum  ex- 
haled. 

OF  THE  FORMS  OF  THE  CELLULAR  SYSTEM  AND  OF  THE 
FLUIDS  IT  CONTAINS. 

Q.  What  is  the  figure  of  the  cells  of  this  texture? 

«#.  There  is  no  uniformity  in  this  respect. 

Q.  What  proves  a  universal  communication  of  these 
cells? 

•tf.  Such  phenomena  as  these  j  the  extension  of  emphy- 
sema; the  emptying  of  a  hydropic  limb  from  one  or  two 


OF    THE    CELLULAR    SYSTEM.  63 

punctures;  the  ascent  and  descent  of  fluids  on  pressure — • 
these  and  other  facts  prove  this  communication  between 
the  cells. 

Q.  By  what  fluids  is  this  texture  exclusively  permeable? 

A.  By  fat  and  serum.  Fluids  do  not  pass  through  this 
texture  from  the  stomach  to  the  skin  and  bladder,  as  has 
been  supposed.  The  vital  forces  of  the  cellular  texture  are 
only  in  relation  to  fat  and  serum. 

Q.  What  part  of  this  texture  is  destitute  of  fat? 

«/?.  The  eyelids,  scrotum  and  prepuce,  bones,  hair,  epi- 
dermis, brain,  spinal  marrow  and  serous  system. 

Q.  Is  there  much  serum  in  the  healthy  state  of  this  tex- 
ture? 

«#.  There  is  not  as  much  as  is  supposed.  Recollect  how 
it  accumulates  in  disease. 

Q.  What  is  the  nature  of  this  serum  ? 

A.   It  is  proved  to  be  albuminous. 

Q.  In  which  muscles,  those  of  animal  or  those  of  or- 
ganic life,  is  there  most  fat  found? 

JL.  There  is  little  in  the  muscles  of  organic  life;  it 
abounds  in  those  of  animal  life. 

Q.  Where  is  fat  almost  exclusively  found  in  infants? 

t/?.  In  the  sub-cutaneous  cellular  texture. 

Q.  Where  is  it  most  abundant  in  adult  life? 

*#.  At  that  period  the  abdominal  fat  is  in  greatest  abun- 
dance. 

Q.   In  old  age  what  becomes  of  the  fat? 

A.  It  disappears;  perhaps  it  is  not  deposited,  or  the  ab- 
sorption may  be  more  active. 

Q.  Is  a  considerable  accumulation  of  fat  to  be  viewed 
as  a  normal  or  abnormal  process? 


64  OP   THE    CELLULAR    SYSTEM, 

»#.  It  is  a  morbid  act,  somewhat  analogous  to  serous 
collections;  it  is  the  result  of  debilitating  causes. 

Q.  To  what  causes  may  unnatural  corpulency  and  ema- 
ciation be  generally  ascribed? 

t#.  The  pathological  reason  is  a  general  or  local  disease 
or  debility  extended  to  the  cellular  texture.  This  disease 
or  debility  may  originate  there. 

Q.  What  curious  phenomenon  is  presented  in  the  cel- 
lular texture  of  some  birds? 

Jl.  The  ortolan  and  other  birds  are  said  to  fatten  very 
suddenly  in  foggy  weather. 

Q.  What  is  the  colour  of  the  fat? 

*/?.  It  is  white  in  early  life,  yellow  in  advanced  life, 
and  at  the  latter  period  it  has  a  peculiar  taste  and  smell. 

Q.  What  causes  tend  to  diminish  the  fat,  or,  in  other 
words,  to  induce  emaciation  ? 

«#.  Protracted  abstinence,  prolonged  organic  affections, 
purulent  collections  depending  on  chronic  malady,  leuco- 
phlegmasia,  the  undue  operation  of  depressing  passions, 
increased  evacuations,  watchings,  great  degrees  of  heat, 
intemperance,  and  many  other  causes  tend  to  emaciate  the 
body. 

Q.  Has  temperature  of  the  body  exclusive  influence  in 
preserving  the  fat  fluid? 

«#.  No;  for  both  cold  and  warm-blooded  animals  have 
the  fat  fluid.  It  is  a  vital  influence  that  keeps  it  liquid. 

Q.  What  do  you  find  frequently  substituted  for  fat  near 
the  heart,  in  hydropic  and  phthisical  patients? 

«#.  A  yellow  transparent  fluid,  of  a  gelatinous  aspect, 
having  many  of  the  characters  of  albumen. 

Q.  How  is  the  fat  formed? 


OF    THE    CELLULAR    SYSTEM.  65 

«/2.  By  exhalation,  through  invisible  vessels  into  the  cel- 
lular texture. 

Q.  What  is  the  adipose  texture,  as  distinct  from  the 
cellular? 

•ft.  It  is  the  texture  in  which  fat  is  formed  and  contained. 

Q.   What  is  the  structure  of  this  adipose  texture? 

•ft.  It  is  a  soft,  white  structure,  manifesting  free  exten- 
sibility and  contractility  of  texture.  It  assumes  the  form 
of  fine,  semi-transparent  laminae.  It  is  filled  with  little 
vesicles  containing  fat. 

Q.  What  evidence  is  there  that  a  peculiar  organization 
is  necessary  for  the  formation  of  fat? 

•ft.  Because  in  many  parts  of  the  cellular  texture  there 
is  no  fat. 

Q.  What  physiological  fact  is  established  by  the  absence 
of  fat  in  many  parts  which  have  been  mentioned  above? 

•ft.  Its  presence  would  destroy  or  impede  their  functions. 

Q.  Are  the  adipose  vesicles  impermeable? 

A.  They  are;  for  though  the  fat  be  rendered  fluid,  if 
the  adipose  vesicle  be  unbroken,  it  does  not  escape.  In 
this  it  differs  from  the  permeability  of  the  cellular  texture. 

Q.  Is  there  any  other  material  feature  in  which  the  adi- 
pose and  cellular  textures  differ? 

•ft.  Yes;  the  uses  of  the  adipose  are  partial,  those  of  the 
cellular  are  general. 

Q.  What  is  the  chemical  nature  of  fat? 

•ft.  It  is  composed  of  stearine  and  elaine,  of  sebacic, 
margaric,  and  oleic  acid. 

Q.  What  are  soaps? 

•ft.  Salts  formed  by  the  uniojn  of  these  acids  with  the 
base  that  is  used. 

9, 


66  OF    THE    CELLULAR    SYSTEM- 


Organization  of  the  Cellular  System. 

Q.  What  is  the  organization  of  the  cellular  texture? 

*ft.  See  the  answer  to  the  first  question  on  this  tissue; 
but  it  may  be  added  here,  that  there  is  great  diversity  of 
sentiment  on  this  topic.  Of  late,  some  distinguished  ana- 
tomists have  supposed  it  a  homogeneous  gelatinous  sub- 
stance, without  evident  organization. 

Q.  Where  have  you  the  best  view  of  the  organization 
of  this  cellular  texture? 

«/2.  A  part  of  the  scrotum  is  the  fittest  part,  as  it  has  no 
fat  in  it. 

Q.   Are  the  laminae  of  this  texture  delicate? 

A.  Yes;  as  much  so  as  vesicles  of  soap  and  water  blown 
from  a  pipe. 

Q.  What  are  the  filaments  composed  of? 

«#.   They  are  absorbents  and  exhalents. 

Q.  What  are  the  evidences  of  the  organic  nature  of  this 
texture? 

«/?.   Its  liability  to  disease. 

Q.  In  what  portions  of  this  texture  are  fat  and  serum 
deposited? 

t#.  In  addition  to  what  has  been  said,  above  of  the  adi- 
pose texture,  it  may  be  observed,  that  these  fluids  are  de- 
posited in  little  cells,  which  form  reservoirs;  these  cells 
are  composed  of  the  transparent,  non-filamentous  layers. 
The  cells  containing  fat  are  impermeable,  those  with  se- 
rum freely  communicate  with  each  other. 

Q.  What  remarkable  tendency  is  manifested  by  the  fila- 
ments and  lavers  of  the  cellular  texture  ? 


OF    THE    CELLULAR    SYSTEM.  67 

Ji.  They  absorb  the  moisture  of  the  atmosphere,  as  may 
be  seen  in  dissecting  rooms  in  moist  weather. 

Q.   How  is  this  texture  classed? 

*#.   Among  the  white  organs  yielding  much  gelatine. 

Q.  What  are  the  effects  of  air,  putrefaction,  maceration, 
and  ebullition,  on  this  texture? 

«/#.  It  is  altered  more  slowly  by  exposure  to  these,  than 
any  of  the  white  organs.  It  putrefies  less  readily;  by  long 
boiling  it  melts. 

Q.   Is  it  easily  changed  by  the  digestive  processes? 

«/#.  It  is  not;  compared  with  many  other  textures  it  is 
indigestible. 

Q.  What  are  the  parts  common  to  the  organization  of 
the  cellular  texture? 

*ft.   Blood-vessels,  exhalents,  absorbents,  and  nerves. 

Q.  Which  vessels  are  most  numerous? 

A.  The  exhalents,  and  by  their  extensive  function,  they 
render  this  texture  the  seat  of  frequent  and  various  dis- 
orders. 

Q.  What  evidences  the  existence  of  absorbents  in  this 
texture? 

*ft.  The  removal  of  fat  and  serum,  the  absorption  of 
dropsical  serum,  and  of  ecchymosis;  the  removal  of  mild 
injected  fluids;  the  disappearance  of  emphysema,  and  the 
drying  up  of  ulcers. 

Q.  Are  the  absorbents  numerous  in  proportion  to  the 
quantity  of  cellular  texture  in  a  part  ? 

A.  Yes ;  in  the  brain,  where  there  is  little  of  this  tex- 
ture, you  find  few  absorbents,  perhaps  none. 


OP    THE    CELLULAR    SYSTEM- 


Properties  of  the,  Cellular  Texture. 

1.    Textural  Properties. 

Q.  What  are  the  textural  properties  of  this  tissue? 

t#.  Extensibility  and  contractility. 

Q.  How  is  cellular  extensibility  evidenced  ? 

JL.  In  fatty  and  serous  cellular  infiltrations,  and  in  the 
extension  of  this  texture  in  moving  the  limbs. 

Q.   Where  is  this  extensibility  most  evident? 

«#.  In  the  cellular  tissue,  under  the  skin,  and  between 
the  muscles.  It  is  slight  in  the  sub-mucous  texture. 

Q.   Is  this  property  suddenly  or  slowly  manifested? 

t#.  In  some  instances  with  great  rapidity,  as  you  see  in 
emphysema,  and  in  cases  of  sudden  tumefaction  from 
fractures, 

Q.  What  opposes  the  rupture  of  this  texture? 

«/?.  Its  extensibility,  and  a  species  of  locomotion,  by 
which,  if  too  violently  drawn,  it  displaces  the  contiguous 
cellular  texture,  draws  it,  and  thus  it  is  less  extended. 

Q.  Under  what  circumstances  does  it  Iqse  this  extensi- 
bility? *J . 

*ft.  In  several  diseases,  such  as  inflammation  and  can- 
cer, &c.  Y' 

Q.  At  what  period  is  the  contractility  of  texture  great- 
est in  this  tissue? 

J2.  In  youth:  it  loses  it  in  advanced  life.  The  wrin- 
kles of  old  age  are  owing  to  the  cellular  texture  not  con- 
tracting as  in  youth,  so  as  to  confine  the  skin  close  to  the 
subjacent  organs. 


THE    CELLULAR    SYSTEM.  69 


2.    Vital  Properties. 

Q.  Does  this  texture  possess  much  animal  sensibility  ? 
«#.  Not  in  its  healthy  condition;  but  it  is  very  evident 
in  the  pain  which  attends  phlegmon. 

Q.   What  proves  the  existence  of  organic  sensibility? 
t/?.  The  exhalation  and  absorption  of  fat,  serum,  and 
other  liquids  are  the  operations  of  organic  sensibility. 

Q.  What  instances  show  that  all  fluids  have  not  the 
same  relation  to  the  organic  sensibility  of  this  texture  ? 

Ji.  Some  foreign  fluids,  as  blood,  milk,  and  lymph,  do 
not  excite  that  property  beyond  the  absorbing  point; 
while  others,  as  wine,  urine,  &c.  carry  it  speedily  to  in- 
flammation, and  convert  organic  to  animal  sensibility. 

Q.  How  do  you  prove  the  existence  of  insensible  or- 
ganic contractility  in  this  texture? 

t#.  The  phenomena  indicating  organic  sensibility,  de- 
monstrate the  insensible  organic  contractility  j  these  phe- 
nomena are  absorption  and  exhalation. 

Q.  Does  the  cellular  texture  ever  manifest  sensible  or- 
ganic contractility? 

»#.  You  see  it  in  the  scrotum,  which  contracts  on  the 
application  of  cold. 

Q.  On  what  do  the  critical  deposites  frequently  ob- 
served in  acute  diseases,  depend? 

«/2.  On  the  sympathy  of  the  cellular  tissue  with  the 
diseased  organ.  "  A  man  in  the  ward  St.  Charles,  in 
consequence  of  great  terror,  had  a  sudden  contraction 
of  the  epigastric  region;  a  tinge  of  jaundice  spread  over 
his  face  in  a  few  hours.  In  the  evening  he  had  a  great 


70  OF    THE    CELLULAR    SYSTEM. 

oedema,  produced  sympathetically,  by  the  influence  of  the 
liver  on  the  cellular  texture." 

Q.  In  what  manner,  and  at  what  stages  of  their  dis- 
eases, do  the  heart,  lungs,  stomach,  and  liver,  affect  this 
texture? 

'«/?.  Chronic  diseases  of  these  organs  in  the  last  stages, 
induce  debility  of  the  cellular  texture,  with  serous  infiltra- 
tions; this  is  a  sympathetic  result. 

Q.  What  inference  relative  to  the  cellular  tissue  is 
drawn  from  the  state  of  the  skin  in  chronic  and  acute 
diseases? 

«/?.  That  the  cellular  texture  may  be  similarly  and  sym- 
pathetically affected,  and  be  like  the  skin,  more  or  less 
dry  or  humid,  at  different  periods  of  diseases. 

Q.  What  vital  forces  are  excited  in  passive  cellular 
sympathies? 

<A.  Organic  sensibility  and  insensible  organic  contrac- 
tility, for  these  predominate  in  this  texture.  Sympathetic 
action  and  disease  always  operate  on  the  predominant  vital 
forces  of  a  tissue. 

Q.  You  have  said  that  this  texture  receives  sympathetic 
impressions,  under  what  circumstances  does  it  radiate 
them? 

«#.  When  a  phlegmonous  inflammation  excites  fever, 
gastric  and  hepatic  irritation,  you  have  an  example  of  ac- 
tive cellular  sympathy. 

Q.  How  may  this  active  sympathy  be  profitably  em-- 
ployed ? 

Jl.  In  the  use  of  issues;  for  the  cellular  active  sympa- 
thy from  the  issue,  is  more  powerful  than  those  of  the 
skin  from  a  blister. 


OF    THE    CELLULAR    SYSTEM.  71 

Q.  Why  does  inflammation  progress  more  rapidly  in 
the  cellular  texture  than  in  the  aponeurosis,  tendons,  and 
cartilages? 

t/2.  Because  the  cellular  vital  forces  are  much  more  ac- 
tive than  those  of  the  textures  just  named. 

Q.  Does  cellular  pus  differ  from  cutaneous,  mucous,  and 
osseous  pus? 

€#.  It  does.  Cellular  pus  is  the  ordinarily  received  stan- 
dard for  pure  pus;  but  erroneously,  because  the  different 
textures  throw  out  different  kinds  of  pus,  all  of  which 
are  as  healthy  as  the  cellular. 

Q.  Has  the  cellular  texture  of  each  organ  peculiar  vital 
forces  ? 

«/?.  Certainly  not.  These  forces  differ  only  in  degree; 
being  greater  in  the  cellular  tissue  of  the  skin,  less  in  that 
of  the  cartilages. 

Q.  Why  does  an  artery  escape  suppuration,  though 
soaked  in  pus? 

«#.  Because  arterial  and  venous  cellular  texture  being 
altogether  filamentous,  its  vital  forces  are  not  excitable  to 
the  point  of  inflammation,  as  that  texture  is  which  is  com- 
posed both  of  filaments  and  layers. 

3.   Properties  of  Reproduction. 

Q.  What  remarkable  feature  distinguishes  the  cellular 
texture  from  others? 

t#.  A  property  of  reproduction,  an  elongation,  a  species 
of  vegetation ! ! 

Q.  What  depends  on  this  property? 

Ji.  The  formation  of  cicatrices,  tumours,  cysts,  &c. 

Q.  In  considering  cicatrices,  how  do  you  divide  them? 


72  OP    THE    CELLULAR    SYSTEM. 

•ft.  Into  those  of  the  external,  and  those  of  the  internet, 
organs. 

Q.  What  steps  does  a  wound  take  from  its  formation 
to  its  cicatrization? 

•ft.  Inflammation,  granulation,  suppuration,  depression 
of  surface,  formation  of  pellicle  at  first  red,  then  white. 

Q.  What  purposes  does  inflammation  secure  to  a  wound? 

A.  By  it  the  organic  sensibility  of  the  cellular  texture 
is  raised  to  animal  sensibility;  and  the  insensible  organic 
contractility  is  so  exalted,  that  these  together  excite  the 
reproductive  powers  of  the  texture,  in  the  form  of  granu- 
lations. 

Q.  What  are  granulations? 

•ft.  Not  fleshy  tubercles,  but  small  cellular  vesicles  fill- 
ed with  a  thick  lardaceous  substance. 

Q.  What  is  the  provisional  pellicle  covering  granula- 
tions? 

•ft.  That  which  prevents  the  contact  of  air  while  the 
permanent  cicatrix  is  forming. 

Q.  What  are  the  evidences  of  the  cellular  nature  of 
granulations,  and  of  the  pellicle  that  covers  them  ? 

•ft.  As  granulations  are  the  same  in  every  texture,  and 
as  the  cellular  tissue  is  the  only  one  common  to  all  the 
organs,  it  is  inferred  that  they  are  cellular;  again,  where 
the  cellular  texture  is  most  abundant,  granulations  form 
most  readily;  when  the  cellular  texture  is  removed,  the 
difficulty  of  reproduction  is  great;  maceration  of  the  gra- 
nulating surface  of  a  wound  exposes  this  textural  base. 

Q.  Then  granulations  are  not  elongated  vessels? 

•ft.  No;  they  are  cellular  elongations;  for  the  cellular 
texture  alone  is  capable  of  self-extension,  increase  and  re- 
production. 


THE    CELLULAR    SYSTEM. 


73 


Q.  If  granulations  are  uniformly  cellular  throughout 
the  textures,  how  is  it  that  the  various  organs  are  re- 
newed? 

*#.  In  the  cells  of  these  granulations,  depositions  are 
made  of  the  nutritive  matter,  peculiar  to  the  various 
organs.  For  instance,  when  the  bone  is  broken,  gelatine 
and  phosphate  of  lime  are  thrown  into  the  granulations ; 
if  a  muscle  is  to  be  renewed,  fibrine  is  deposited. 

Q.  Explain  the  difference  in  this  third  period  of  cica- 
trization in  the  internal  and  external  lesions? 

A.  The  third  period  is  that  of  deposition  of  nutritive 
matter  spoken  of  in  the  last  question.  Now,  in  the  inter- 
nal organs,  nutritive  matter  is  deposited;  but  in  external 
lesion,  pus  is  exhaled  and  thrown  off,  as  possessing  no- 
thing nutritive  or  reuniting. 

Q.  In  external  cicatrices,  what  comes  of  the  fatty  mat- 
ter contained  in  the  cells? 

t#.  They  are  emptied  of  it  in  the  process  of  suppura- 
tion. 

Q.  What  follows  this  emptying  of  the  cells? 

«#.  They  sink  and  adhere  to  each  other,  contract,  and 
thus  form  a  uniform  substance  covered  with  a  membrane. 

Q.  When  is  this  membrane  of  the  cicatrix  complete? 

v?.  When  the  adhesion  between  all  the  cells  which  first 
form  the  fleshy  granulations  is  complete;  the  membrane 
is  the  result  of  this  adhesion. 

Q.  Why  is  this  membrane  at  first  red,  then  white? 

A.  Because  at  first  red  blood  circulates  in  the  exhalents; 
after  a  time  it  leaves  them,  and  returns  to  its  own  vessels. 

Q.  What  parts  are  most  favourable  to  the  formation  of 
cicatrices? 

Jl.  Those  where  the  skin  yields  most,  as  the  scrotum. 
10 


74  OF    THE    CELLULAR    SYSTEM. 

Where  the  skin  yields  least,  as  on  the  head,  tibia,  and  ster- 
num, cicatrices  are  largest. 

Q.  How  does  union  by  the  first  intention  differ  from 
cicatrization  ? 

«#.  In  the  union,  the  periods  and  processes  of  cicatriza- 
tion do  not  appear:  the  union  is  by  an  agglutination  of  the 
sides  of  the  wound. 

Q.   By  what  property  do  cicatrices  contract  ? 

«#.  By  organic  contractility  in  the  cellular  vesicles. 

Q.  What  is  fungous  flesh  ? 

»#.  Exuberant  formations  of  cellular  vesicles  in  wounds 
and  ulcers. 

Q.  Whence  and  what  are  polypi? 

«#.  These  and  all  other  excrescences  arise  from  a  mor- 
bid reproductive  effort,  or  spontaneous  elongation  of  the 
cellular  texture. 

Q.  How  do  you  account  for  the  differences  in  tumours? 

t#.  They  arise  from  the  variety  of  deposites  made  in 
the  elongated  cellular  texture. 

Q.  Is  there  no  way  to  account  for  this  variety  in  the 
deposites  ? 

*#.  It  depends  on  the  degree  of  the  vital  forces  in  the 
elongated  textures;  a  higher  exercise  of  these  forces  pro- 
ducing one  deposite,  a  lower  another. 

Q.  But  are  there  not  tumours  independent  of  this  elon- 
gating action  of  the  cellular  texture  ? 

A.  Yes;  those  of  a  chronic  character,  from  infiltration 
of  the  cellular  texture. 

Q.   What  is  a  cyst? 

A.  A  membranous  sac  without  opening,  developed  ac- 
cidentally; cysts  contain  fluids  of  different  sorts. 

Q.  What  texture  forms  them  ? 


OP    THE    CELLULAR    SYSTEM.  75 

.#.  The  cellular.  They  resemble  the  serous  membranes, 
and  they  are  cellular. 

Q.  What  analogies  prove  the  identity  of  cysts  and  se- 
rous membranes? 

.#.  Their  conformation:  their  structure,  for  maceration 
and  inflation  prove  cysts  to  be  cellular;  they  have  few 
blood-vessels  and  many  exhalents.  The  vital  properties 
prove  the  identity ;  they  are,  in  a  natural  state,  destitute 
of  animal  sensibility,  but,  like  serous  membranes,  when 
inflamed  they  have  it  exquisitely;  cysts  have  much  or- 
ganic sensibility.  The  functions  of  cysts  confirm  the  iden- 
tity, these  are  absorption  and  exhalation.  Diseases  prove 
the  similarity,  their  pathological  states  resemble  those  of 
serous  membranes. 

Q.  Can  you  demonstrate  that  absorption  takes  place  in 
cysts? 

•/#.  If  it  does  not,  how  are  the  fluids  in  encysted  dropsy 
removed  ? 

Q.  How  are  cysts  formed? 

•#.  Not,  as  is  commonly  supposed,  by  the  gradual  de- 
position of  a  fluid  in  a  cell  of  the  cellular  texture,  but  by 
a  departure  from  the  common  process  of  increase  in  the 
tissue  which  they  resemble;  and  in  which  these  cysts  are 
formed. 

Q.  What  relation  then  is  there  between  the  growth  of 
a  cyst,  and  the  increase  of  the  fluid  contained  ? 

A.  The  membranous  sac  is  first  deposited;  the  exhalents 
begin  to  throw  out  fluid,  and  as  these  vessels  increase  in 
the  membrane  the  fluid  is  increased,  and  consequently  the 
encysted  tumour  enlarges. 


76  OF    THE    CELLULAR    SYSTEM. 


DEVELOPMENT  OF  THE  CELLULAR  TEXTURE. 

Q.  What  is  its  aspect  in  the  earliest  foetal  period? 

.#.  It  predominates  almost  exclusively  in  the  primor- 
dial mucous  mass.  It  is  at  first  mucous,  then  gluey,  then 
cellulur  texture  appears.  It  becomes  less  fluid  as  the  foetus 
grows. 

Q.  What  is  the  nature  of  the  fluid  so  abundant  in  the 
cellular  texture,  early  after  conception? 

A.  It  is  albuminous  and  gelatinous. 

Q.  Is  the  foetus  ever  emphysematous? 

JL.  The  delicacy  of  the  cellular  layers  prevents  this 
state;  they  burst  rather  than  bear  the  pressure  of  air  in 
the  cells. 

Q.  What  is  the  condition  of  the  vital  energy  of  this 
texture  in  youth  and  infancy? 

t/2.  Very  active;  hence  wounds  speedily  cicatrize,  se- 
rous infiltrations  are  rapidly  removed,  dropsies  seldom 
occur  in  infancy,  tumours  form  and  increase  rapidly.  The 
vital  forces  are  energetic. 

Q.  What  is  the  cause  of  the  roundness  of  form  which 
characterizes  the  infant? 

ifl.tThe  quantity  of  cellular  texture  concealing  the 
organs. 

Q.  What  change  does  after  and  advanced  age  produce 
on  this  texture? 

t/2.  It  becomes  firmer,  more  condensed,  and  diminishes 
in  proportion. 

Q.   In  what  temperament  does  it  preponderate  ? 

*#.  In  the  phlegmatic  or  lymphatic. 

Q-   Is  it  more  abundant  in  males  or  females? 


OF    THE    CELLULAR    SYSTEM-  77 

•ft.  In  females,  hence  the  roundness  of  their  forms. 

Q.  Whence  the  laxity  of  the  cellular  texture  in  old  age? 

•ft.  It  arises  from  the  loss  of  its  vital  forces,  particularly 
organic  contractility. 

Q.  Whence  the  emaciation  of  age  ? 

•ft.  The  cellular  texture  dries,  decays,  withers  away. 

Q.  Where  are  osseous  incrustations  in  this  texture  most 
frequently  found  ? 

•ft.  In  the  texture  between  the  uterus  and  rectum. 


PATHOLOGY  OF  THE  CELLULAR  TISSUE. 

Q.  What  are  the  principal  diseases  of  this  texture? 

•ft.  Phlegmon,  carbuncle,  furuncle,  scleremia,  ulcers, 
anasarca,  oedema,  haemorrhage,  morbid  fatness,  emaciation, 
emphysema,  wens,  cysts,  steatoma,  atheroma,  meliceris, 
and  sometimes  hydatids. 

Q.  To  what  part  of  the  cellular  tissue  do  you  allude 
when  you  speak  of  its  diseased  state ? 

•ft.  Principally  to  that  found  in  the  interstices  of  parts. 

Q.  What  texture  of  the  body  is  exclusively  subject  to 
swelling? 

•ft.  The  cellular;  the  swelling  of  all  tissues  is  owing  to 
the  cellular  which  enters  into  their  composition. 

Q.  How  are  diseases  extended  from  one  organ  to  an- 
other? 

•ft.   By  means  of  the  cellular,  continuous  texture. 

Q.  What  divisions  will  you  make  of  the  diseases  of  the 
cellular  texture? 

•ft.  Into  idiopathic,   symptomatic,  and  diseases  from 


76  OF    THE    CELLULAR    SYSTEM. 

continuity  of  tissue.  Phlegmonous  inflammation  indicates 
the  idiopathic;  the  spread  of  carcinoma,  the  continuous; 
and  serous  effusion  from  organic  disease,  the  sympto- 
matic. 

Q.  What  are  the  symptoms  of  phlegmon? 

•ft.  Swelling,  redness,  pain,  induration,  heat,  pulsation ; 
sometimes  general  and  gastric  symptoms. 

Q.   How  does  phlegmon  terminate? 

•ft.  In  resolution,  most  frequently  in  suppuration,  in 
chronic  inflammation  of  the  cellular  texture,  with  or  with- 
out serous  effusion,  and  in  gangrene. 

Q.  Is  pus  at  once  immediately  deposited  in  the  cavity 
of  an  abscess  ? 

•ft.  It  is  first  formed  in  little  cells,  which,  gradually 
communicating,  form  the  cavity  of  an  abscess. 

Q.  What  do  you  mean  by  carbuncle? 

•ft.  A  tumour  having  its  seat  in  the  sub-cutaneous  cel- 
lular texture. 

Q.  What  are  the  distinguishing  symptoms  of  car- 
buncle? 

•ft.  A  liyid  colour,  greater  hardness  than  phlegmon, 
phlyctense  appear  on  its  surface,  the  skin  is  gangrenous, 
the  discharge  is  ichorous,  the  pain  is  peculiarly  hot,  the 
general  strength  of  the  patient  is  much  reduced. 

Q.  Does  carbuncle  depend  alone  on  the  intensity  of  the 
inflammation? 

•ft.   It  does  not ;  there  is  a  poisonous  cause,  or  specific 
one,  concerned  in  the  production  of  anthrax. 
-  Q.  There  is  a  recent  speculation  as  to  the  cause  of  the 
eschar  in  carbuncle,  what  is  it? 

*ft.  It  is  that  the  portion  of  cellular  texture  composing 
the  eschar,  is  in  an  incarcerated,  or  strangulated  condition 


OF    THE    CELLULAR    SYSTEM.  79 

Q.  What  do  you  mean  by  furuncle? 

«#.  It  is  an  inflammation  in  the  cellular  tissue  and  der- 
moid  texture,  less  violent,  of  slower  progress  than  phleg- 
mon, occurring  sometimes  several  at  a  time,  and  does  not, 
like  phlegmon,  leave  a  cicatrix, 

Q.  What  parts  are  exempt  from  furuncle? 

t#.  The  palms  of  the  hands,  the  soles  of  the  feet,  and 
the  cranium. 

Q.  What  do  you  understand  by  scleremia? 

JL.  An  induration  of  the  sub-cutaneous  cellular  texture 
of  infants,  when  an  incision  throws '  out  yellow  fatty 
serum. 

Q.  To  what  has  this  disease  been  ascribed? 

t/2.  To  syphilitic  taint,  to  deranged  perspiratory  func- 
tion, and  to  an  affection  of  the  respiratory  process,  to  an 
opening  of  the  foramen  ovale. 

Q.  What  do  you  mean  by  an  ulcer? 

«#.  It  is  a  suppuration  of  a  wound  or  injury,  which  is 
prolonged  after  the  ordinary  stages  of  inflammation  have 
been  completed. 

Q.  What  are  ulcers  owing  to? 

*#.   To  a  chronic  inflammation  of  the  cellular  texture. 

Q.  What  materially  influences  the  condition  of  ulcers? 

*fl.  The  peculiar  vital  forces  of  different  parts. 

Q.   How  is  cellular  dropsy  divided? 

«/?.  Into  general  and  partial. 

Q.  Where  do  you  find  dropsy  most  frequently  ? 

«#.  In  the  most  dependant  parts  of  the  cellular  texture. 

Q.  What  are  other  divisions  of  dropsy  ? 

«#.  It  is  idiopathic  and  sympathetic.  It  is  symptomatic 
of  fever  and  of  organic  disease. 


80  OP    THE    CELLULAR    SYSTEM. 

Q.  Is  the  cellular  tissue  altered  in  dropsy? 

&.  It  is  not;  the  cells  are  only  distended  with  the  in- 
creased exhalation  of  serum. 

Q.  To  what  are  the  sudden  swellings  in  fractured  limbs 
and  contusions  owing? 

•#.  Neither  to  an  cedematous  nor  emphysematous  state 
of  the  cellular  texture,  but  to  "a  peculiar  excitation 
of  it." 

Q.  How  do  you  account  for  swelling  of  the  belly  in 
enteritis? 

«#.  It  is  owing  to  a  swelling  of  the  sub-cutaneous  cellu- 
lar tissue. 

Q.  What  portion  of  the  cellular  texture  is  most  liable 
to  inflammation? 

,/#.  The  sub-cutaneous. 

Q.  What  state  of  the  cellular  texture  does  obesity  in- 
dicate? 

*fl.  A  debility  in  the  tissue,  and  an  undue  disposition  to 
deposite  fat. 

Q.  Whence  does  leanness,  emaciation,  arise? 

«#.  From  organic  diseases,  but  not  of  those  of  the  brain 
or  heart.  It  proceeds  commonly  from  organic  disease  of 
the  abdominal  viscera,  and  of  the  lungs.  Emaciation  is 
usually  symptomatic.  You  know  that  the  depressing 
passions  induce  emaciation. 

Q.  At  what  part  does  emphysema  commence? 

Jl.  Always  near  the  thorax,  near  the  lungs.  Fractures 
of  the  ribs,  wounds  of  the  chest,  and  vehement  vocal  ex- 
ertions cause  it. 

Q.  What  tumours  form  in  the  cellular  tissue? 

•#.  Wens  and  cysts. 


OP    THE    CELLULAR    SYSTEM.  81 

Q.   What  is  the  base  of  the  fluids  of  wens? 

A.  It  is  albuminous. 

Q.  Are  the  sub-mucous,  sub-serous,  or  vascular  cellu- 
lar tissues  often  diseased? 

•#.  You  never  see  disease  of  the  sub-mucous  cellular 
tissue,  unless  when  an  abscess  forms  near  the  rectum 
In  the  sub-serous,  matter  forms  more  commonly,  and  it 
points  externally;  while,  to  prevent  the  pus  finding  its 
way  into  the  serous  cavities,  that  tissue  is  thickened.  The 
sub-vascular  cellular  tissue  is  never  diseased. 


11 


NERVOUS  SYSTEM. 

Q.   How  should  the  general  nervous  system  be  divided? 
.#.   Into  that  belonging  to  animal  life,  and  that  attached 
to  organic  life. 

I.   NERVOUS  SYSTEM  OP  ANIMAL  LIFE. 

Q.  What  is  the  centre  of  the  nervous  system  of  animal 
life,  and  what  are  the  parts  to  which  it  is  distributed  ? 

J2.  The  brain  and  its  dependencies  form  the  centre, 
and  the  nervous  system  of  animal  life  is  distributed  to  the 
senses  and  the  organs  of  voluntary  motion. 

Q.  What  is  the  centre  of  the  nervous  system  of  organic 
life,  and  where  are  the  nerves  distributed? 

Jl.  The  ganglions  are  the  central  points,  and  the  nerves 
are  distributed  to  the  organs  of  digestion,  circulation,  res- 
piration, and  secretion. 

Q.  Is  the  distinction  in  nervous  distribution  preserved 
with  unvarying  precision?  > 

t/?.  There  are  a  few  comparatively  unimportant  devi- 
ations. 

Q.  Name  a  leading  peculiarity  in  this  nervous  system 
of  animal  life. 

•ft..   Its  symmetrical  character;  the  nerves  go  off  in  pairs. 

Q.  What  renders  this  duplicate  organization  evident? 

«/?.  Dissection  and  disease  exhibit  the  right  and  left 
nervous  system  of  animal  life.  In  palsy  one  side  will  be 
affected,  while  the  integrity  of  the  other  side  is  unimpaired. 


NERVOUS    SYSTEM.  83 

Q.  What  relation  does  the  size  of  the  brain  bear  to  the 
nerves,  in  man  and  quadrupeds? 

«/#.  It  is  in  an  inverse  proportion.  In  man,  the  brain  is 
very  large  in  proportion  to  his  nerves;  in  quadrupeds,  ge- 
nerally, the  brain  is  small  and  the  nerves  large. 

Q.  What  is  the  result  of  this? 

«/#.  That  although  brutes  are  superior  in  some  of  the 
senses  to  man,  man  in  the  sense  of  touch  surpasses  animals 
greatly.  Touch  implies  intellect  beyond  instinct;  hence 
the  perfection  of  the  organs  of  touch  and  the  development 
of  the  brain,  are,  in  man,  in  proportion  to  each  other. 

External  forms  of  the,  Nervous  System  of  Animal  Life. 

Q.  From  what  part  of  the  brain  do  the  cerebral  nerves 
originate? 

A.  From  the  cerebrum,  tuber  annulare  and  its  conti- 
nuations, and  from  the  medulla  spinalis. 

Q.  To  what  opinion  did  this  origin  of  these  cerebral 
nerves  give  rise? 

t#.  As  none  originated  from  the  cerebellum,  the  cere- 
brum was  said  to  be  the  source  of  the  voluntary,  and  the 
cerebellum  that  of  the  involuntary  motions. 

Q.  To  what  nerves  does  the  cerebrum  give  rise? 

Jl.  To  the  olfactory  and  the  optic. 

Q.  For  what  are  these  nerves  remarkable? 

t/?.  Their  adhesion  is  firm  at  their  origin  from  the  brain, 
and  they  are  much  softer  than  most  of  the  other  nerves. 

Q.  What  nerves  arise  from  the  tuber  annulare  and  its 
elongations? 

«#.  The  motores  communes  of  the  muscles  of  the  eye, 
the  pathetici,  the  trigemini,  the  motores  externi  of  the  eye, 


84  NERVOUS    SYSTEM. 

the  facial,  the  auditory,  the  par  vagum,  the  glosso-pha- 
ryngeal,  and  the  great  hypoglossal. 

Q.  Is  the  adhesion  of  these  nerves  to  the  brain  strong? 

«/?.  No;  they  are  so  weak  as  to  be  torn  by  the  raising 
of  the  pia  mater. 

Q.   What  nerves  arise  from  the  spinal  marrow? 

*&.  The  cervical,  eight  pairs  in  number;  the  dorsal, 
twelve  pairs;  five  sets  of  lumbar;  five  or  six  sacral;  in  all 
amounting  to  thirty  or  thirty-one  pairs.  The  spinal  nerve, 
so  called,  which  penetrates  the  cranium  and  again  emerges 
from  it,  also  arises  from  the  spinal  marrow. 

Q.   Are  the  nerves  elongations  of  the  brain? 

«/?.  They  are  not;  they  are  formed  cotemporaneously 
with  the  brain,  and  are  independent  organs  communicat- 
ing with  the  brain. 

Q.  What  has  given  rise  to  the  opinion  of  the  decussa- 
tion  of  all  the  nerves? 

Jl.  The  supposition  is  founded  on  the  fact,  that  paralysis 
occurs  on  the  side  of  the  body  opposite  to  the  hemisphere 
of  the  brain  that  is  injured. 

Q.   Does  anatomy  prove  this  decussation? 

Ji.  It  does  not. 

Q.  Does  palsy  in  the  motion  of  a  limb  necessarily  in- 
volve loss  of  sensation  in  the  member? 

•#.   It  rarely  suspends  sensibility. 

Q.  On  what  do  discordant  hearing  and  vision  often 
depend? 

Jl.  Frequently  on  a  diseased  condition  of  the  organ  af- 
fected, which  does  not  involve  a  morbid  state  of  the  brain. 

Q.  What  membranes  are  found  about  the  nerves? 

&.  The  dura  mater  invests  them  to  their  exit  from  the 
brain  and  spine.  The  tunica  arachnoides  envelopes  thr 


NERVOUS    SYSTEM.  85 

nerves  from  their  connexion  or  junction  with  the  brain, 
to  their  exit  from  the  bony  canal.  The  pia  mater  con- 
tinues on  the  nerves. 

Q.  How  do  the  tunics  of  the  optic  nerve  differ  from 
those  of  other  nerves? 

Ji.  It  has  a  fibrous  investment  from  its  origin  to  the 
sclerotic  coat. 

Q.-  What  nerves  converge  after  their  origin? 

*ft.  The  olfactory;  all  the  rest  remain  separate. 

Q.  What  nerves  go  to  their  destination  without  com- 
municating with  other  nerves  ? 

•ft.   The  olfactory,  the  optic  and  auditory. 

Q.  Do  the  nerves  of  the  spine  make  their  egress  imme- 
diately opposite  their  origin  ? 

«#.  They  do  not;  the  lower  or  lumbar  run  several 
inches  in  the  spinal  canal  before  they  leave  it. 

Q.  Of  what  practical  import  is  this  fact? 

•ft.  In  order  that  moxa  should  be  applied  at  the  origin 
of  the  nerves,  the  immediate  exit  of  the  cervical  from  the 
spine,  and  the  long  course  within  the  spinal  column  which 
the  lumbar  pursue  before  their  exit,  should  be  well  known. 

Q.  How  are  the  plexuses  of  the  spinal  nerves  formed  ? 

«#.  By  each  nerve  sending  a  branch  to  the  one  above 
and  below  it. 

Q.  How  do  you  best  understand  the  distribution  of  the 
spinal  nerves? 

Jl.  By  taking  them  as  they  arise  from  the  plexuses  and 
not  regarding  them  as  pairs  of  nerves. 

Q.  Are  the  plexuses  confined  to  those  at  the  exit  of  the 
nerve  ? 

*fl.  No — other  communicating  chords  form  as  the  nerves 
proceed  in  their  course. 


86  NERVOUS    SYSTEM. 

Q.   0£  what  are  the  nervous  trunks  composed  ? 

«/#.  Chords  and  filaments. 

Q.  Do  the  chords  of  a  nervous  trunk  communicate  ? 

*ft.  They  do  by  filaments.  The  chords  which  end  the 
trunk  are  not  composed  of  the  same  filaments  which  com- 
menced them. 

Q.  Why  do  you  object  to  the  opinion  of  their  being 
distinct  nervous  chords  which  serve  for  sensation  and  mo- 
tion? 

*#.  The  inter-communication  of  the  filaments  forbids 
the  supposition. 

Q.  What  do  you  mean  by  the  termination  of  the  nerve? 

«#.  The  point  where  each  filament  ends. 

Q.  How  many  modes  of  termination  have  filaments  ? 

«tf.  They  have  three;  with  other  filaments  of  the  same 
system;  with  filaments  of  the  system  of  ganglions,  forming 
anastomoses;  and  filaments  lose  themselves  in  the  organs. 

Q.  How  are  the  filamentary  nervous  communications 
to  be  distinguished? 

Jl.  There  are  those  of  real  anastomosis,  and  those  of 
juxta-position  and  contiguity. 

Q.  Why  are  sympathies  not  exclusively  ascribed  to 
nervous  anastomoses  ? 

J2.  Because  these  anastomoses  are  rare,  compared  with 
the  numerous  and  diversified  sympathies,  normal  and  ab- 
normal. 

Q.  How  many  kinds  of  anastomosis  are  there? 

»/#.  There  are  three;  viz.  that  formed  by  two  branches 
of  different  nerves;  the  anastomosis  formed  by  the  branches 
of  the  same  nerve ;  and  the  one  which  arises  from  the  union 
'of  two  nerves  of  the  same  pair,  or  of  different  pairs  at  the 
median  line. 


NERVOUS    SYSTEM.  87 

Q.  Where  is  this  median  anastomosis  seen  ? 

Ji.  In  the  superficial  nerves  of  the  neck  and  chin. 

Q.  What  feature  in  paralysis  does  this  median  anasto- 
mosis explain  ? 

Jl.  Probably  some  mobility  in  a  part  which  is  affected 
with  paralysis. 

Q.  What  systems  are  destitute  of  nerves? 

«#.  The  cartilaginous,  the  fibre-cartilaginous,  the  pi- 
lous, the  epidermoid,  and  others,  are  unprovided  with 
nerves. 

Q.  What  peculiarity  is  found  in  the  terminations  of  the 
optic,  olfactory,  and  auditory  nerves  ? 

Jl.  The  pulp  of  these  nerves  is  expanded  on  the  organs 
without  the  covering  of  the  nerve. 

I 
Organization  of  the  Nervous  System  ofJlnimal  Life, 

Q.  What  is  the  organization  of  the  nerves  of  animal 
life? 

A.  Filaments  in  apposition  form  chords,  and  chords  in 
apposition  form  trunks  of  nerves. 

Q.  Is  the  internal  organization  of  the  nerves  uniform? 

«#.  It  is  not — it  is  singularly  diversified. 

Q.  What  is  the  organization  of  each  nervous  filament  ? 

*ft.  An  external  membrane  forming  a  canal;  containing 
the  medullary  matter  or  pulp. 

Q.  What  is  the  nature  and  origin  of  the  nervous  coat? 

t#.   It  is  the  pia  mater  of  the  brain  and  spinal  marrow. 

Q.  What  are  the  three  great  modifications  of  the  pia 
mater  ? 

«/?.  On  the  gray  substance  surrounding  the  brain  and 
cerebellum  it  is  red,  highly  vascular,  loose,  and  easily  se- 


83 


NERVOUS    SYSTEM. 


parated  and  raised  up  ;  on  the  white  substance  which  in- 
vests the  tuber  annulare  and  its  four  elongations  received 
from  the  brain  and  cerebellum,  it  is  not  so  red,  it  becomes 
firmer,  more  adherent,  not  so  easily  torn;  on  the  spinal 
marrow  and  nerves  it  increases  in  density,  becoming  whit- 
ish and  resisting. 

Q.  What  purpose  does  this  density  of  the  spinal  pia 
mater  subserve? 

«#.  It  serves  as  a  protection  and  support  to  the  spinal 
marrow,  especially  where  the  marrow,  not  filling  the  ver- 
tebral canal,  would,  without  this  firm  coat,  be  liable  to 
concussion. 

Q.  What  effects  have  acids  on  this  nervous  coat? 

Jl.  They  harden  it  immediately,  but  it  soon  regains 
its  softness.  Water  hardens  the  nerves  exposed  to  its  ac- 
tion. 

Q.  Whence  does  the  medullary  matter  of  the  nerves 
originate? 

£.  It  is  continuous  with  the  medulla  of  the  brain  and 
spinal  marrow. 

Q.  In  what  nerves  is  it  most  abundant? 

•ft..  In  the  auditory  and  optic  nerves.  In  the  progress  of 
a  nerve  to  its  termination  it  diminishes. 

Q.  What  general  influence  has  loss  of  natural  moisture 
on  the  whiteness  of  parts? 

«/?.   It  destroys  their  whiteness. 

Q.  In  what  respects  do  the  cerebral  and  nervous  me- 
dullary substances  differ  and  agree  ? 

•#..  The  cerebral  medulla  putrefies  soon,  the  nervous 
slowly.  Acids  harden  both;  alkalies  soften  them.  The  ce- 
rebral substance  is  digestible;  the  nerve  is  not. 

Q.  Is  the  medulla  the  same  in  all  the  nerves? 


NERVOUS    STSTF  89 

JJ.  It  appears  to  differ,  in  different  nerves,  in  consist- 
ence, in  the  degree  of  moisture,  in  its  colour,  and  other 
particulars. 

Q.  On  what  does  the  different  sensibility  of  the  various 
parts  depend  ? 

*#.   On  the  diversity  of  organization  in  the  parts,  on  the 
different  organization  of  the  nerves,  and  on  the  varying , 
consistence  and  appearances  of  the  medullary  matter. 

Q.   Is  the  nervous  medulla  a  fluid? 

«#.  It  resembles  jelly,  vjt  is  more  like  a  fluid  than  a 
solid. 

Q.  Have  the  nerves  cellular  texture? 

*ft.  In  the  interior  of  the  brain  and  spine  there  is  none. 
When  the  nerves  emerge  from  the  cranium  and  spine, 
they  have  much  cellular  tissue  around  the  trunks, 'chords, 
and  filaments.  Perhaps  the  nervous  coat  is  the  cellular 
texture  condensed. 

Q.   How  do  the  arteries  supply  the  nerves  ? 

<ft.  Blood-vessels  pass  between  the  chords  to  supply  the 
filaments. 

Q.  What  influence  has  arterial  blood  on  the  nerves? 

*ft.  It  is  to  the  nerve  what  blood  is  to  every  organ ;  the 
stimulus  which  supports  and  perpetuates  functional  power. 

Q.  What  influence  has  an  increased  determination  of 
blood  to  the  nerves? 

.#.  It  increases  nervous  action,  and  when  the  determi- 
nation is  very  great  it  overwhelms  it. 

Q.   How  is  the  nervous  medulla  formed  ? 

«#.  The  arteries  of  the  nerves  deposite  in  the  exha- 
lents  this  nervous  matter,  which  is  then  thrown  out. 

Q.  Then  the  nervous  coat  does  not  secrete  it  ? 

.#.   The  nervous  coat  has  no  more  agency  in  secreting 


90  NERVOUS    SYSTEM. 

the  nervous  medulla,  than  the  pia  mater  has  in  \secreting 
the  substance  of  the  brain. 

Q.  Does  the  brain  supply  the  nervous  medulla? 

«#.  On  the  contrary,  it  has  been  just  said  that  the  me- 
dulla is  deposited  by  the  arteries  of  the  nerve. 

Q.  What  pathological  facts  does  this  arterial  nutrition 
of  the  nerves  explain  ? 

Ji.  It  accounts  for  the  preservation  of  the  inferior  por- 
tion of  a  cut  nerve;  for  the  continued  nutrition  of  a  nerve 
from  which  cerebral  communication  has  been  cut  off  by 
ligature;  and  for  the  uninterrupted  support  of  a  nerve, 
which,  in  palsy,  may  have  ceased  to  correspond  with  the 
brain.  The  secretion  of  nervous  medulla,  and  the  nutri- 
tion of  nervous  organization  by  the  arteries,  explain  these 
facts. 

Properties  of  the  Nervous  System  of  Animal  Life. 

Q.  Do  the  nerves  manifest  much  textural  property  ? 

<&.  They  do  not.  If  extension  be  suddenly  made,  it  is 
dangerous,  but  if  gradually  applied,  it  is  borne  to  a  consi- 
derable degree.  The  nerves  possess  little  contractility  of 
texture. 

Q.   How  is  nervous  sensibility  divided? 

Jl.   Into  inherent  and  common. 

Q.  In  what  part  of  a  nerve  does  animal  sensibility  re- 
side? 

•fl.  In  the  medullary  substance;  the  nervous  coat  has 
very  little.  This  medullary  substance  has  animal  sensi- 
bility to  a  very  great  degree. 

Q.  Why  are  nerves  not  painful  when  surrounded  by 
fluids,  tumours,  or  when  exposed  to  the  air? 


NERVOUS    SYSTEM.  91 

JL.  Because  there  is  so  little  animal  sensibility  in  the 
nervous  coat. 

Q.  What  effect  has  repeated  irritation  on  the  animal 
sensibility  of  nerves? 

«/?.  It  is  gradually  diminished,  and  by  rest  is  reac- 
cumulated. 

Q.  What  are  the  peculiarities  of  nervous  animal  sensi- 
bility? 

J2.  Observe  the  peculiarity  of  pain  in  the  different  or- 
gans; how  the  sensation  of  pain  in  the  dermoid  texture, 
for  instance,  differs  from  that  in  the  muscular  or  osseous 
texture.  Another  feature  interesting  to  the  physician  and 
surgeon  is,  that  the  trunk  of  a  nerve  partially  irritated, 
the  animal  sensibility  will  often  be  exalted  in  all  the 
branches;  as  when  pain  is  felt  along  the  forearm  when 
the  cubital  nerve  is  compressed  or  struck  at  the  elbow; 
this  is  further  illustrated  in  tic  doloureux,  and  in  irritation 
of  points  of  the  sciatic  nerve.  In  these  the  irritated  point 
is  a  centre  from  which  painful  irradiations  are  diffused. 

Q.  Does  the  increase  of  animal  sensibility  ever  take 
place  between  the  injured  point  and  the  brain? 

*fl.  It  does  not;  it  is  an  affection  continued  along  the 
branches. 

Q.  What  example  is  given  to  illustrate  the  different 
animal  sensibility  or  pain  in  different  textures  ? 

t/#.  The  case  of  a  man  is  related  by  Bichat,  who  in  the 
course  of  an  amputation,  asked  the  surgeon  why  it  was 
that  the  pain  in  cutting  through  the  skin  was  so  different 
from  that  felt  in  the  division  of  the  muscles. 

Q.  How  many  kinds  of  sensation  arise  from  the  inter- 
nal sensitive  principle? 

•#.  Two — the  external  and  internal. 


92  NERVOUS    SYSTEM, 

Q.   How  are  the  external  sensations  divided  ? 

4#.  Animal  sensibility  with  regard  to  external  sensa- 
tions is  general  and  particular.  The  general  refers  to 
impressions  made  by  bodies  on  the  external  surface.  The 
particular  relates  to  the  sensibilities  of  particular  organs 
to  peculiar  impressions,  as  the  eye  to  light. 

Q.  But  have  not  some  organs  of  animal  life  both  gene- 
ral and  peculiar  animal  sensibility? 

*ft.  They  have.  For  instance,  the  tongue  may  feel  the 
impression  of  a  substance,  without  the  sense  of  taste  being 
excited.  The  nerves  of  general  and  peculiar  sensibility 
are  absolutely  distinct. 

Q.  How  does  opium  relieve  pain? 

«/?.  By  suspending  the  action  of  the  brain,  so  that  nei- 
ther external  nor  internal  sensations  are  perceived. 

Q.   Do  the  nerves  possess  animal  contractility? 

•A.  Not  at  all;  that  property  appertains  to  the  muscles. 

Q.  What  agency  then  have  the  nerves  in  the  muscular 
animal  contractility? 

Ji.  They  transmit  the  principle  of  motion.  In  animal 
contractility  there  are  three  agents;  viz.  the  brain  that 
wills,  the  nerve  conveying  cerebralvolition,  the  muscle 
which  obeys  in  action. 

Q.  Do  the  nerves  exercise  much  organic  contractility 
and  sensibility? 

<flL.  They  do  not.  They  exercise  these  properties  of 
life  so  far  as  nutrition  requires  them.  The  nerves  abound 
with  animal  sensibility. 

Q.  Is  there  a  difference  in  the  size  of  the  nerves  of  a 
sound  and  paralytic  side? 

„     •#.  They  are  alike.     The  nerves  are  not  affected  in 
many  diseases.     Their  nutrition  goes   on,   and  organic 


NERVOUS    SYSTEM,  93 

sensibility  is  so  little  increased  as  not  to  enlarge  the  ner- 
vous trunks. 

Q.  In  what  abnormal  condition  did  Bichat  once  find 
the  sciatic  nerve? 

*#.  With  the  veins  of  the  nerve  in  a  varicose  state. 

Q.  Do  the  cerebral  nerves  affect  the  organic  sensibility 
of  textures? 

•/?.  They  do  not;  that  property  of  the  textures  is  be- 
yond the  sphere  of  those  nerves. 

Q.  Recapitulate  the  functions  over  which  organic  sen- 
sibility presides? 

«#.  It  supports  capillary  circulation;  secretion;  exhala- 
tion; absorption;  nutrition. 

Q.  What  excites  these  functions? 

4/2.  The  fluids  excite  the  organic  sensibility  of  the  so- 
lids, which  last  in  action  exercise  insensible  organic  con- 
tractility. 

Q.  What  general  considerations  induce  the  belief  that 
the  nerves  of  animal  life  do  not  preside  over  and  influence 
these  functions? 

«#.  They  are  said  to  receive  no  impulse  from  the  nerves 
of  animal  life,  because  no  filaments  from  these  nerves  go 
to  the  capillaries;  some  of  these  organic  functions  are 
most  active  during  sleep,  at  which  time  the  animal  ner- 
vous system  is  quiescent;  and  cartilages  which  receive  no 
nerves  have  nutrition  as  well  as  other  parts. 

Q.  Over  what  diseases  do  organic  sensibility,  and  in- 
sensible organic  contractility  preside? 

•#.  Over  tumours,  dropsies,  morbid  sweating,  haemor- 
rhagies,  disorders  of  secretion,  and  such  like  affections. 

Q.  What  diseases  arise  from  disordered  animal  sensi- 
bility and  contractility  ? 


94  NERVOUS    SYSTEM. 

•#.  Spasm,  convulsion,  palsy,  somnolency,  .torpor,  de- 
rangement of  the  intellectual  functions;  in  a  word,  every 
thing  which  tends,  in  disease, to  interrupt  our  relations  with 
surrounding  bodies;  these  belong  to  alterations  of  animal 
sensibility  and  contractility. 

Q.  Does  proneness  to  inflammation  depend  on  the  num- 
ber of  nerves  in  a  part? 

A.  Those  parts  which  have  the  greatest  number  of 
nerves  are  not  most  liable  to  inflammation. 

Q.  What  do  you  understand  by  sympathy? 

*#.  It  is  an  impression  in  health  or  disease,  not  arising 
from  a  natural  connexion  of  functional  operation ;  the  im- 
pression is  conveyed  from  an  organ  to  the  nervous  sys- 
tem, or  a  portion  thereof. 

Q.   How  do  the  nerves  sympathize  in  disease? 

•ft.  There  is  a  sympathy  between  two  nerves  of  the 
same  pair;  as  when  one  optic  nerve  induces  the  other  to 
sympathy.  Again,  two  nerves  of  the  same  side,  but  not 
of  the  same  trunk,  sympathize,  as  when  blindness  results 
from  the  injury  of  the  frontal  nerve.  Again,  two  branches 
of  one  trunk  sympathize  with  each  other;  and  nerves 
sympathize  actively  and  passively  with  other  organs. 

Q.  What  is  the  rationale  of  nervous  sympathy  on  re- 
mote parts  ? 

*ft.  Nervous  sympathy  operates  on  the  predominant 
vital  properties  of  the  parts  engaged;  increasing  animal 
sensibility  in  pain  of  the  head;  or  animal  contractility 
in  sympathetic  convulsions;  or  sensible  organic  contrac- 
tility in  the  action  of  the  heart,  or  in  contractions  of  the  sto- 
mach in  vomiting.  These,  in  different  cases  and  persons, 
are  excited  by  irritation  of  a  nerve. 

Q.  What  have  been  considered  the  media  of  sympathy  ? 


NERVOUS    SYSTEM.  95 

*ft.  Nervous  anastomoses,  vascular  communications,  or 
the  continuity  of  cellular  and  mucous  tissue. 

Q.  What  is  the  most  rational  division  of  sympathies? 

A.  Into  those  which  actuate  animal  and  organic  sensi- 
bility and  contractility. 

Q.  Can  you  explain  the  sympathies  of  animal  sensibi- 
lity? 

t/f?.  They  depend  on  an  irregularity  or  derangement  of 
perception  in  the  brain,  by  which,  an  impression  made  on 
one  part,  is  referred  to  another;  nervous  communication  is 
not  necessary  to  this. 

Q.  On  what  does  the  sympathy  of  animal  contractility 
depend  ? 

«tf.  The  impression  is  made  on  the  muscles  through  the 
brain. 

Q.  Are  nerves,  when  cut,  reproduced? 

A.   They  are,  as  other  parts  are. 

Q.   How  are  external  sensations  transmitted  ? 

«#.  Uniformlyifcy  the  nerves.  The  internal  sensations 
are  conveyed  in  an  unknown  manner. 

Development  of  the  Nervous  System  of  Animal  Life. 

Q.  What  is  the  state  of  the  brain  and  nerves  in  the 
foetus? 

«#.  Inactive,  but  much  developed.  The  nerves  in  in- 
fancy are  much  larger  in  proportion  to  the  body,  than 
those  at  adult  life ;  so  likewise  is  the  brain. 

Q.  What  remarkable  change  takes  place  in  the  animal 
nervous  system  at  birth? 

«/?.  In  foetal  life  it  is  supplied  with  black  blood,  at  the 
commencement  of  independent  life  it  has  red  blood. 


96  JTCRVOITS    SYSTEM. 


Q.  This  red  blood  performs  two  functions  on  the  brain 
—  what  are  they? 

»/?.  It  contributes  nutrition  to  the  brain,  and  excitation 
as  a  stimulant 

Q.  What  is  necessary  to  the  commencement  of  animal 
life? 

Ji.  That  the  organs  be  influenced  by  red  blood. 

Q.  What  cooperates  with  this  red  blood  to  excite  ani- 
mal life  at  birth  ? 

•#.  External  impressions,  and  those  made  on  the  mu- 
cous surfaces. 

Q.  What  is  the  conspicuous  feature  in  asphyxia? 

.#.  The  apparent  absence  of  animal  life. 

Q.   How  does  asphyxia  differ  from  foetal  life? 

*fl.  In  the  foetus,  organic  life  goes  on.  The  blood  dif- 
fers in  the  foetus  from  the  black  blood  of  asphyxia  —  one, 
the  foetal,  is  a  natural  state  of  the,  black  blood,  the  other  is 
a  morbid  state. 

Q.  What  functions  predominate  in  irtfoncy? 

t/?.  The  animal;  hence  a  constant  susceptibility  to  exter- 
nal impressions;  the  constant  action  of  the  voluntary  mus- 
cles, in  the  desire  to  touch  and  grasp  what  is  seen  ;  hence 
the  predominance  of  the  diseases  of  the  animal  functions, 
the  frequency  of  cerebral  disease  and  convulsions. 

Q.  Why  do  infants  sleep  so  frequently  and  so  much? 

•#.  The  activity  of  the  animal  functions  fatigues  the 
brain,  demands  repose,  and  produces  sleep. 

Q.  Are  the  same  systems  predominant  at  different  pe- 
riods of  life? 

A.  They  are  not.  The  brain  and  nerves  predominate 
in  infancy;  the  uterus  in  the  girl;  the  lungs  in  robust  man- 
hood; the  gastric  viscera  in  advanced  life. 


NERVOUS    SYSTEM,  97 

Q.  Why  does  so  great  a  portion  of  blood  go  to  the  brain 
in  infancy? 

«#.  The  predominance  of  the  vital  forces  of  the  brain 
invites  it. 

Q.  What  is  the  comparative  consistence  of  the  brain  in 
foetal  and  senile  life? 

&  Nearly  fluid  in  the  foetus,  it  becomes  quite  firm  in 
old  age,  being  progressive  in  its  change  from  the  fluid  to 
the  firm  state.  The  vascularity  of  the  animal  organs  di- 
minishes with  age;  their  colour  becomes  dull.  These 
changes  take  place  in  the  brain  as  well  as  nerves. 

Q.  Give  a  brief  account  of  the  formation  of  the  cerebral 
mass. 

Ji.  The  hemispheres  of  the  brain  assume  on  their  first 
development  the  membranous  form.  The  gray  or  cortical 
substance  is  formed  subsequently  to  the  white.  The  me- 
dullary substance  of  the  brain,  and  the  white  substance  of 
the  medulla  spinalis,  are  filamentous  and  fibrous.  The 
structure  of  the  cortical  substance  is  not  yet  ascertained, 
perhaps  it  is  fibrous. 

Q.  What  is  the  chemical  composition  of  the  cerebral  mass? 

Ji.  It  is  composed  of  a  white,  shining  fatty  matter;  of  a 
smaller  portion  of  a  red  fatty  substance;  of  water,  albumen, 
osmazone,  sulphur,  phosphate  of  potash,  lime,  magnesia, 
with  some  appearances  of  muriate  of  soda. 

Q.  State  briefly  Beclard's  view  of  some  points  in  the 
nervous  structure. 

«#.  He  states  that  the  nervous  filaments  do,  at  their  ori- 
gin, penetrate  into  the  substance  of  the  brain.  The  nerves 
probably  arise  from  the  gray  substance,  not  from  the  me- 
dullary. The  nervous  filaments  of  the  medulla  oblongata 
do  decussate.  The  nervous  texture  is  composed  of  globules. 

13 


98  NERVOUS    SYSTEM. 

Q.  What  are  the  principal  pathological  states  of  the 
brain? 

«/#.  The  brain  is  diminished  in  concussion,  so  as  not  to 
fill  the  cranium.  The  brain  is  subject  to  a  softening,  as  well 
as  to  an  induration  of  its  substance.  The  brain  suppurates, 
forms  tumours,  tubercles,  osseous  depositions.  BICHAT 
had  the  lobes  of  the  brain  of  very  unequal  size.  The 
nerves  are  enlarged  in  some  cases,  and  atrophic  in  others. 
The  nerves  cicatrize,  but  are  never  preternaturally  pro- 
duced. 


II.  NERVOUS  SYSTEM  OF  ORGANIC  LIFE, 
General  Remarks. 

Q.   How  should  the  ganglions  be  considered? 

*fl.  Each  as  a  distinct  centre  distributing  or  receiving 
nerves. 

Q.  How  does  the  system  of  organic  nerves  differ  from 
the  nerves  of  animal  life? 

«,#.  In  the  system  of  animal  life  the  brain  is  a  single 
centre;  in  that  of  organic  life  there  are  as  many  centres 
as  ganglions.  In  animal  life  the  nerves  are  symmetrical, 
in  the  organic  system  they  are  irregular.  The  nerves  of 
organic  life  do  not  serve  for  sensation,  as  those  of  animal 
life  do.  The  nerves  of  organic  life  have  no  connexion 
with  voluntary  locomotion,  the  animal  nerves  control  this. 
The  organic  system  of  nerves  belongs  to  internal  life,  the 
animal  nerves  to  the  external  or  life  of  relation.  Lastly, 
ganglions  are  not  found  in  the  head. 


NERVOUS    SYSTEM.  99 

Q.  Is  the  sympathetic  properly  termed  a  nerve? 
*4.  It  is  not  one  nerve;  it  is  a  series  of  nerves  derived 
from  the  ganglions  or  little  brains. 

Of  the  Ganglions. 

Q.  What  are  the  ganglions? 

Jl.  The  ganglions  are  small  bodies  of  a  red  or  gray  co- 
lour, deeply  situated  along  the  vertebral  column  and  well 
protected;  and  from  them  are  sent  numerous  nervous  ra- 
mifications. They  are  not  moveable. 

Q.  What  do  these  ganglions  or  ramifications  form  ? 

Jl.   That  which  is  termed  the  great  sympathetic  nerve. 

Q.   What  ganglions  are  uniformly  found? 

«/?.  The  superior  cervical,  the  semilunar,  the  ophthal- 
mic; others  are  sometimes  wanting. 

Q.  What  is  the  form  of  these  bodies? 

«#.  They  are  irregularly  formed  ;  sometimes  round,  or 
flat. 

Q.  Is  the  organization  of  the  ganglion  and  cerebral 
substance  similar? 

Jl.  They  are  not  alike  in  this  respect.  The  ganglions 
are  susceptible  of  the  horny  hardening  as  solids  are;  the 
cerebral  substance  does  not  admit  that  change.  The 
ganglions  are  not  fibrous,  the  cerebral  substance  is. 

Q.  What  is  Scarpa's  opinion  of  the  organization  of  the 
ganglions  ? 

«#.  That  they  are  a  kind  of  expansion  of  the  filaments 
of  the  nerves.  Bichat  thinks  not,  but  says  they  are  homo- 
geneous and  sui  generis. 

Q.  How  do  the  ganglions  differ  from  the  ganglionic 
nerves  ? 


100  NERVOUS    SYSTEM. 

«#.  In  their  colour,  consistence  and  properties. 

Q.   What  kind  of  membrane  envelopes  the  ganglions? 

\fi.  The  cellular  membrane,  resembling  the  sub-mucous 
and  arterial  cellular  coat. 

Q.  What  are  the  vital  properties  of  the  ganglions? 

*#.  Organic  sensibility  and  insensible  organic  contrac- 
tility. 

Q.  What  proves  that  they  are  destitute  of  animal  sen- 
sibility? 

t/?.  Biehat  opened  a  dog;  he  irritated  the  semilunar 
ganglion,  without  giving  the  animal  pain:  he  irritated  a 
cerebral  nerve,  it  excited  great  pain. 

Q.  What  important  division  is  to  be  made  in  the  gene- 
ral class  of  nervous  disorders? 

«/?.  They  are  divisible  into  those  which  arise  from  the 
nerves  of  animal,  and  those  from  the  nerves  of  organic 
life. 

Q.  Name  several  of  the  diseases  of  the  nerves  of  ani- 
mal life? 

A.  Convulsions,  palsy,  hemiplegia,  tetanus,  catalepsy, 
apoplexy,  and  the  greater  number  of  epilepsies,  disorders 
of  sight,  hearing,  taste,  smell. 

Q.  Now  present  some  of  the  diseases  of  the  nerves  of 
organic  life. 

•ft.  Hysteria,  hypochondriasis,  melancholy,  diseases  of 
the  abdomen  and  chest.  Reflect  on  the  difference  in  the 
two  classes  of  diseases  alluded  to  in  this  and  the  preced- 
ing question. 

Q.\  Does  the  pain  felt  in  the  viscera  of  organic  life  dif- 
fer from  that  in  the  viscera  of  animal  life? 

«#.  It  does.  The  intestinal  pains,  those  felt  in  the  loins 
from  uterine  affection,  the  burning  at  the  stomach,  all  dif- 


NERVOUS    SYSTEM.  101 

fer  much  from  the  pain  of  the  organs  of  animal  life.  There 
is  like  difference  in  convulsive  actions  of  animal  and  or- 
ganic life. 

Q.  Is  the  ganglionic  system  developed  as  early  as  the 
brain? 

«/!?.  By  no  means.  The  ganglions,  when  first  develop- 
ed, are  not  as  soft  as  the  foetal  brain. 

Q.  What  pathological  inference  is  deducible  from  the 
earlier  development  of  the  cerebral  organ? 

«#.  That  diseases  of  the  animal  nervous  system  prevail 
in  infancy,  from  the  early  development  of  that  system. 

Q.  Does  the  connexion  of  the  nerve  with  the  ganglion 
resemble  that  of  the  nerves  with  the  brain? 

t/?.  The  nerves  are  more  firmly  united  to  the  ganglions 
than  the  cerebral  nerves  are  to  the  brain.  The  nerves  of 
organic  life  differ  much  more  from  the  ganglion  than  the 
cerebral  nerve  does  from  the  brain. 

Q.  What  do  you  mean  by  cerebral  ganglions? 

Ji.  An  enlargement  of  the  spinal  nerves  at  their  exit 
from  the  spine;  their  organization  resembles  the  organic 
ganglions,  but  they  differ  in  sensibility.  For  example,  if 
the  superior  or  inferior  cervical  ganglion  be  irritated,  the 
muscles  supplied  by  them  remain  unaffected:  irritate  a  ce- 
rebral ganglion,  and  behold  the  convulsions  which  will  be 
excited. 

Of  the  Nerves  of  Organic  Life. 

Q.  What  is  the  course  of  the  organic  nerves? 

*/l.  They  communicate  with  the  nerves  of  animal  life; 
then  each  ganglion  sends  nerves  to  the  next  ganglion,  with 
one  exception;  some  nerves  go  to  the  cerebral  muscles,  the 


102'  NERVOUS    SYSTEM. 

diaphragm,  and  some  muscles  of  the  neck;  they  intercom- 
municate chiefly  so  as  to  form  plexuses,  into  which  the 
animal  nerves  send  a  few  branches. 

Q.  In  any  plexus  do  the  animal  nerves  predominate? 

e/?.   In  the  pulmonary  the  par  vagum  does. 

Q.  How  do  you  account  for  the  innumerable  interfac- 
ings of  the  organic  nerves? 

•#.  The  filaments  are  not  generally  united  in  a  trunk, 
as  the  animal  nerves  are;  the  first  run  separately,  not  bound 
in  bundles. 

Q.  What  is  remarkable  in  the  course  of  the  organic 
nerves  ? 

•ft.  They  surround  the  arteries  for  some  distance,  like 
a  net-work.  It  is  not  so  with  the  cerebral  nerves,  which 
are  in  apposition  only  with  the  vessels. 

Q.  What  effects  proceed  from  this  reticular  nervous  en- 
velope around  the  vessels? 

«/?.  The  motion  of  the  blood  may  have  some  effect  on 
the  nerves.  In  support  of  this  opinion  it  may  be  remark- 
ed, that  as  nature  has  placed  a  great  number  of  arteries  at 
the  base  of  the  brain,  to  agitate  it  with  an  alternate  mo- 
tion, she  has  also  put  the  most  considerable  plexus  of  the 
whole  organic  system  upon  one  of  the  places  to  which  the 
red  blood  communicates  the  strongest  impulse,  viz.  upon 
the  trunk  of  the  coeliac  artery. 

Q.  What  is  the  structure  of  the  organic  nerves? 

t/?.  Some  are  in  chords,  like  the  animal;  others  are  gray 
or  red  filaments,  and  are  very  numerous. 

Q.  What  vital  properties  have  these  nerves? 

Jl.  They  have  neither  animal  sensibility,  nor  sensible 
organic  contractility.  They  have  organic  sensibility,  and 
insensible  organic  contractility. 


NERVOUS    SYSTEM.  103 

Q.  What  inference  is  made  from  the  universal  existence 
of  these  ganglions? 

A.  That  they  subserve  some  great  though  unknown 
purpose  in  the  animal  economy. 

Q.  What  views  does  Beclard  add  to  this  nervous  sys- 
tem of  organic  life? 

«#.  He  does  not  consider  it  a  settled  point,  that  the 
sympathetic  is  an  independent  nerve;  its  character  may 
be  only  that  of  different  organization. 

Q.  What  are  his  views  of  the  relations  of  the  filaments 
and  nerves  to  the  ganglions? 

*#.  It  is  proved  that  nerves  and  filaments  do  pass  through 
the  ganglions. 


PATHOLOGY  OF  THE  NERVOUS  SYSTEMS  OF  ANIMAL  AND 
ORGANIC  LIFE. 

Q.   Name  the  principal  diseases  of  the  brain. 

JL.  Inflammation,  congestion,  softening,  hardening, 
scirrhus,  ossification,  cartilaginous  transformation,  fungus, 
apoplexy,  epilepsy,  hydatids  of  the  choroid  plexus,  dila- 
tation of  the  arteries  and  veins,  effusions  of  blood  and 
serum,  head-ache,  diminished  volume  of  the  brain. 

'Q.  What  general  observation  will  apply  to  many  of 
these  affections? 

A.  That  many  of  them  are  consequences  of  the  acute 
and  chronic  inflammations  of  the  brain. 

Q.  What  is  the  first  division  of  the  diseases  of  the 
nervous  system? 


104  NERVOUS    SYSTEM, 

«/?.  Into  those  of  the  nervous  system  of  animal  life,  and 
those  of  the  nervous  system  of  organic  life. 

Q.  How  are  the  diseases  of  the  animal  nervous  system 
subdivided'? 

«#.  Into  the  diseases  of  the  brain  and  those  of  the 
nerves. 

Q.  Then  what  is  the  division  of  the  diseases  of  the 
brain? 

«#.  Into  the  idiopathic  or  essential,  and  the  symptoma- 
tic or  consequential. 

Q.  What  are  the  forms  of  inflammation  of  the  brain? 

«/?.  They  are  acute  and  chronic;  but  as  separate  from 
inflammation  of  the  cerebral  meninges — little  is  known  of 
phrenitis. 

Q.  In  the  collection  of  cerebral  diseases  given  above, 
which  are  the  effects  of  inflammation  ? 

«/?.  A  softening,  hardening,  scirrhus,  effusions  of  blood 
and  serum,  and  head-ache,  and  formations  of  pus. 

Q.  After  apoplexy,  what- parts  are  most  liable  to  hemi- 
plegia? 

«#.  The  face  and  extremities;  the  trunk  is  seldom  affect- 
ed with  hemiplegia. 

Q.  What  does  paralysis  essentially  indicate? 

rf.  It  is  symptomatic  of  a  lesion  of  the  nerves. 

Q.  What  is  apoplectic  stertor  owing  to? 

t/?.   To  paralysis  of  the  muscles  of  the  larynx. 

Q.  What  inference  do  spontaneous  alvine  evacuations 
justify  in  a  case  of  apoplexy? 

t/?.  That  the  bowels  and  sphincters  are  losing  their  con- 
tractility. 

Q.  If  an  apoplectic,  bloody  effusion  takes  place  in  a 


NERVOUS    SYSTEM.  105 

young  person,    what  favourable   termination  often   hap- 
pens? 

JZ.  The  clot  is  encysted,  absorbed,  and  the  cavity  final- 
ly obliterated  by  an  adhesion  of  the  sides  of  the  cyst. 

Q.  When  are  bloody  effusions  found  in  the  brain? 

»#.  They  are  found  in  the  substance  of  the  cerebral 
mass,  not  in  the  exterior,  nor  in  the  ventricles. 

Q.  What  fluid  is  usually  found  in  the  ventricles  and  on 
the  external  surface  of  the  brain? 

«#.  Serum;  and  when  this  effusion  is  superficial,  its 
source  is  the  pia  mater,  but  the  serum  in  the  ventricles  is 
always  from  the  arachnoid. 

Q.  What  disease  does  serous  effusion  in  the  brain  con- 
stitute, and  what  in  the  spinal  canal? 

*#.  In  the  brain  it  is  termed  hydrocephalus;  in  the  spi- 
nal column  it  is  hydrorachitis. 

Q.  What  is  the  pathology  of  those  head-aches,  which, 
in  gastric  affections,  so  severely  afflict  the  forehead  and 
one  eye? 

.#.  They  are  sympathetic  affections  of  the  mucous  mem- 
brane of  the  frontal  sinuses,  and  of  the  mucous  membrane 
on  the  eye-ball. 

Q.  How  do  you  divide  alienation  of  mind? 

%#.  Into  the  congenital  and  acquired. 

Q.  What  causes  the  congenital  alienation  ? 

*#.   Organic  derangement. 

Q.  What  hardening  of  the  brain  is  most  common? 

«#.   A  white  fibrous  hardening  in  the  white  substance. 

Q.  What  alteration  in  volume  does  the  brain  undergo? 

•#.  It  diminishes,  but  never  morbidly  enlarges  in  its 
volume. 

Q.  What  are  the  diseases  of  the  nerves? 
14 


106  NERVOUS    SYSTEM. 

t/?.  They  are  the  tic  doloureux,  inflammation,  convul- 
sive affections,  osseous  and  cartilaginous  transformations, 
atrophy,  and  hypertrophy. 

Q.  What  is  the  pathology  of  tic  doloureux  ? 

«#.  It  is  not  known,  but  it  has  been  ascribed  to  an  en- 
gorgement of  the  neurilema. 

Q.  How  do  you  distinguish  tic  doloureux  from  rheuma- 
tism? 

.#.  Tic  doloureux  does  not  change  its  locality,  as  rheu- 
matism does. 

Q.  How  are  nervous  convulsions  distinguished  from 
cerebral? 

«#.  The  nervous  are  local  .in  their  causation  and  extent, 
the  cerebral  are  general. 

Q.   To  what  diseases  are  the  ganglia  subject? 

«#.   To  atrophy  and  hypertrophy. 

Q.  What  changes  are  the  nerves  subject  to? 

A.  To  ossification  and  cartilaginous  alteration  from  in- 
flammation. 


(    107    ) 

VASCULAR  SYSTEM. 

L    VASCULAR  SYSTEM  WITH  RED  BLOOD. 
General  Remarks  upon  the  Circulation. 

Q.  How  is  the  circulation  divided? 

«/?.  Into  that  conveying  red,  and  that  which  circulates 
black  blood. 

Q.  Where  does  the  vascular  system  with  red  blood 
commence? 

t#.  It  arises  in  the  capillaries  of  the  lungs,  and  ends  in 
the  arterial  terminals  or  capillaries  throughout  the  body. 

Q.  Where  is  the  commencement  and  ending  of  the  vas- 
cular system  with  black  blood  ? 

t/2.  It  has  its  origin  in  the  general  capillary  system,  and 
ends  in  the  lungs. 

Q.  What  are  the  channels  for  conveying  the  red  blood  ? 

&.  The  pulmonary  veins ;  the  left  side  of  the  heart  and 
arteries. 

Q.  Is  there  one  continued  or  general  membrane  in  these 
canals? 

«/?.  There  is;  the  lining  membrane  is  continued  from 
one  capillary  system  to  another.  This  membranous  canal 
is  strengthened  on  the  pulmonary  veins  by  loose  mem- 
brane, in  the  heart  by  its  fleshy  walls,  in  the  arteries  by  a 
dense,  fibrous,  peculiar  coat! 

Q.  What  are  the  channels  for  the  system  of  black 
blood? 


108  VASCULAR    SYSTEM. 

Jl.  The  veins,  the  right  side  of  the  heart,  and  the  pul- 
monary artery. 

Q.  How  are  the  valves  of  the  veins  and  arteries  formed? 

,#.  They  are  formed  from  the  continued  lining  mem- 
brane of  these  vessels. 

Q.  What  is  the  conspicuous  anatomical  view  to  be  taken 
of  those  two  circulations? 

«#.  Their  entire  separation,  their  distinctness,  and  the 
respective  origin  and  terminations  of  the  two  in  the  pul- 
monary and  general  capillary  systems. 

<J.  What  do  you  mean  by  their  distinct  and  separate 
character? 

*#.  It  is,  that  separate  organization  supports  them.  Even 
if  the  right  and  left  sides  of  the  heart  were  not  united,  the 
two  functions  would  readily  proceed. 

Q.  At  what  point  in  the  channels  of  the  respective  cir- 
culations do  you  find  the  greatest  collection  of  blood? 

A.  In  the  heart. 

Q.  What  general  arrangement  of  the  channels  is  worthy 
of  recollection  ? 

Jl.  That  the  vessels  which  convey  red  blood  from  the 
commencement  of  its  circulation  to  the  heart  increase  in 
size  and  diminish  in  number;  that  the  vessels  which  con- 
vey red  blood  from  the  heart  to  its  termination  increase 
in  number  and  diminish  in  size.  The  same  fact  obtains 
in  the  arrangement  of  the  vessels  conveying  black  blood, 
viewing  its  vascular  system  as  commencing  in  the  general 
capillaries  and  terminating  in  the  lungs. . 

Q.  What  renders  the  heart  necessary  in  these  two  red 
and  black  blood  systems? 

*#.  Without  it  the  parietes  of  the  vessels  could  not  con- 
vey the  blood  from  one  capillary  system  to  another. 


VASCULAR    SYSTEM.  109 

Q.   What  then  is  the  use  of  the  heart? 

./?.  It  is  purely  to  give  a  mechanical  impulse  to  the 
blood. 

Q.  Where  do  you  find  this  impulsive  power  greatest? 

A.  In  that  circulation  which  is  the  most  extensive:  the 
left  ventricle  has  therefore  more  power  than  the  right. 

Q.  Has  the  heart  any  influence  on  the  qualities  of  the 
blood? 

A.  It  is  not  probable  that  any  effect  is  produced  on  the 
blood  by  the  action  of  the  heart  other  than  a  more  intimate 
mixture  of  its  particles. 

Q.  Can  you  suppose  a  case  in  which  the  heart  could  be 
dispensed  with? 

.#.  The  agency  of  the  heart  is  required  by  the  extent 
of  the  circulations  of  red  and  black  blood;  as  these  are  less 
extensive,  the  impulsive  influence  of  the  heart  will  in  pro- 
portion be  dispensed  with;  in  no  other  view  can  the  idea 
suggested  by  the  question  be  admitted. 

Q.  Is  there  any  motion  independent  of  the  heart's  im- 
pulse ? 

A.  There  is  an  oscillatory  motion  as  in  the  branches 
which  terminate  in  the  porta  of  the  liver;  this  oscillation 
keeps  up  circulation  in  syncope. 

Q.  What  are  the  general  uses  of  the  circulation  with 
red  blood? 

Ji.  It  supplies  the  materials  for  secretion  and  nutrition. 
The  motion  of  the  arteries  which  convey  red  blood  is  use- 
ful in  aiding  functional  action. 

Q.  Does  the  red  blood  furnish  the  material  for  secretion 
to  every  organ? 

Ji.  To  all  except  the  liver. 


110  VASCULAR    SYSTEM. 

Q.  What  are  the  general  uses  of  the  circulation  with 
black  blood? 

t/?.  It  is  a  reservoir  for  the  various  substances,  from 
within  and  without,  which  enter  into  the  venous  blood, 
such  as  the  fluids  from  the  lymphatics,  from  the  thoracic 
duct,  the  chyle,  &c. 

Q.  Under  what  circumstances  will  the  chylous  vessels 
take  up  deleterious  substances? 

«/?.  If  the  organic  sensibility  is  altered  or  exalted,  these 
vessels  will  receive  that  which  in  health  they  would  re- 
ject. Thus  it  is  with  the  skin,  when  it  absorbs  matters, 
and  they  go  into  the  black  blood  circulation. 

Q.  Bring  the  circulations  into  nearer  relation. 

«#.  The  circulation  of  black  blood  receives  materials 
into  the  system,  while  that  of  red  blood  expends  them 
on  it. 

Q.  How  does  this  explain  plethora? 

«/?.  If  the  black  blood  circulation  receives  more  than  the 
red  blood  expends,  there  is  plethora;  on  the  contrary,  an 
impoverished  state  of  the  humours  shows  itself  when  the 
red  blood  expends  more  than  the  black  blood  receives. 

Situation,  Forms,   and  General  Arrangement  of  the 
Vascular  'System. 

Q.  Why  does  gangrene  more  frequently  appear  in  the 
lower  extremities,  than  in  the  head  and  upper  extremities? 

*ft.  Because  in  the  lower  extremities  the  impulse  of  the 
heart  in  the  circulation  is  weakened,  and  the  free  return 
of  blood  is  opposed  by  gravity. 

Q-   How  is  the  aorta  united  to  the  heart? 


VASCULAR    SYSTEM.  Ill 

«/?.  By  means  of  the  internal  or  lining  membrane;  the 
fibrous  membrane  of  the  aorta  does  not  unite  directly  with 
the  fleshy  substance  of  the  heart. 

Q.  How  are  the  semilunar  valves  formed? 

*#.  By  the  folds  of  the  lining  membrane,  and  the  cor- 
responding festoons  of  the  fibrous  membrane  of  the  aorta. 

Q.  What  advantage  results  from  the  undivided  trunk  of 
the  aorta  descendens? 

t/2.  The  impulsive  power  of  the  heart  is  better  preserv- 
ed over  the  great  length  of  the  branches  of  the  inferior 
aorta. 

Q.  What  is  the  most  accurate  estimate  of  the  number 
of  branches  and  subdivisions  of  each  artery? 

«#.  That  made  by  Haller,  amounting  to  twenty. 

Q.  In  ramifications  from  the  main  trunk  of  an  artery, 
what  favours  the  current  of  blood  in  the  branch  ? 

•#.  A  projection  formed  by  the  folds  of  the  internal 
membrane  of  the  artery,  corresponding  with  the  angle 
coming  from  without,  breaks  the  column  of  the  blood  and 
favours  the  change  of  its  current. 

Q.  Does  the  tortuous  course  of  the  arteries  diminish  the 
impetus  of  the  blood? 

*#.  From  experiments. made  on  animals,  it  was  ascer- 
tained that  the  tortuous  course  of  the  arteries  does  not  di- 
minish it. 

Q.  Are  anastomoses  formed  near  to  the  heart,  or  remote 
from  it? 

«/?.  They  are  found  distant  from  the  heart,  and  they  are 
more  numerous  in  those  organs  whose  motions  are  not  con- 
trolled in  any  way  by  other  parts.  You  see  this  exempli- 
fied in  the  arteries  of  the  brain. 

Q.   You  see  the  large  arteries  deep-seated  and  well  pro- 


112  VASCULAR    SYSTEM. 

tected,  is  this  protection  the  only  benefit  derived  by^  the 
arteries? 

<ft.  It  is  not;  for  the  motions  of  the  parts  in  which 
the  yood-vessels  are  imbedded  facilitates  the  passage  of 
blood,  and  the  arterial  pulsation  itself  favours  the  func- 
tional operations  and  vital  activity  of  the  surrounding 
organs. 

Q.  What  are  the  advantages  of  the  tortuous  arterial 
courses? 

«#.  It  serves  to  protect  the  arteries  themselves  from  in- 
jury, in  the  action  of  some  parts;  and  again,  it  in  other 
parts  tends  to  the  safety  of  the  organs. 

Q.   What  is  the  use  of  arterial  anastomosis? 

A.  It  facilitates  the  passage  of  blood  into  the  capillaries, 
whose  vitality  being  so  often  deranged  are  liable  to  con- 
gestion. You  are  well  aware  of  the  value  of  anastomosis, 
after  taking  up  principal  arterial  trunks. 

Q.  Is  the  sum  of  the  diameter  of  the  branches  equal  to 
the  calibre  of  the  trunk? 

•/#.  It  exceeds  it. 

Q.  Why  is  aneurism  more  frequent  in  the  aorta  than  in 
remoter  parts  of  the  arterial  system  ? 

•ft.  Because  in  proportion  to  the  calibre  of  the  artery, 
the  parietes  are  thinner  than  in  the  other  arteries. 

Q.  Where  do  the  arteries  terminate? 

<ft.   In  the  capillaries. 

On  the  Organization  of  the  Vascular  System  with  Red 
Blood. 

Q.  In  what  arteries  is  their  peculiar  coat  thickest? 
•#.  In  the  large  arteries,  and  it  becomes  thinner  in  the 


VASCULAR    SYSTEM.  113 

smaller  ones.  The  inner  or  lining  membrane  is  uniformly 
thick  in  all  the  arteries. 

Q.  In  what  considerable  arteries  is  this  fibrous  coat  thin  ? 

A.   In  the  vertebral  and  internal  carotid. 

Q.  What,  according  to  Bichat,  is  the  source  of  cere- 
bral sanguineous  effusion? 

«/?.  He  supposes  it  always  to  proceed  from  the  capilla- 
ries, not  from  the  arterial  trunks. 

,  Q.  What  is  the  organization  of  this  peculiar  coat  of  the 
arteries? 

«#.  It  is  composed  of  distinct  layers  of  circular  fibres. 
There  are  no  longitudinal  fibres.  The  coat  is  yellow. 

Q.  Is  this  fibrous  coat  of  the  same  texture  with  muscle? 

»#.  It  differs  from  muscle  in  its  firmness,  density,  and 
slight  extensibility.  The  fibrous  coat  will  even  break  be- 
fore it  will  stretch.  There  is  no  analogy  in  their  vital 
properties. 

Q.  What  then  is  this  arterial  coat? 

«#.  Bichat  considers  it  a  distinct  texture. 

Q.  Why  is  the  arterial  structure  so  strong? 

«#.  To  sustain  the  impulse  of  the  heart,  so  that  the  ar- 
teries shall  not  dilate  so  much  as  to  weaken  the  onward 
progress  of  the  blood. 

Q.  Does  similarity  of  form  alone  constitute  similarity 
of  texture? 

«#.  No — similarity  of  properties  is  likewise  necessary. 

Q.  How  does  this  differ  from  the  fibrous  or  peculiar 
coat  of  the  arteries? 

*#.  It  is  thinner;  it  is  transparent;  it  has  no  fibres;  it  is 
white. 

Q.   What  tendency  has  this  coat  in  old  age? 
15 


114  VASCULAR    SYSTEM. 

*ft.  To  ossification,  which  occurs  most  frequently  about 
the  aorta  and  mitral  valves. 

Q.  What  renders  the  pulse  so  intermitting  in  old  age? 

tfl.  It  is  probably  owing  to  this  ossification  of  the  lining 
membrane. 

Q.  Does  this  ossification  of  the  lining  membrane  equally 
endanger  the  old  man  and  the  rniddle-aged  ? 

«#.  That  ossification  which  is  not  alarming  in  the  old, 
is  exceedingly  dangerous  to  the  adult. 

Q.  What  cellular  investments  have  the  arteries  ? 

*fl.  There  is  a  loose  cellular  envelope  which  connects 
them  with  surrounding  parts,  and  a  dense  cellular  coat. 

Q.  Does  cellular  substance  enter  into  the  organization 
of  the  fibrous  coat? 

«/?.  It  does  not;  hence  the  brittleness  of  that  coat,  and 
its  disposition  to  rupture  in  aneurism. 

Q.  Why  are  not  absorbents  found  in  the  arteries? 

A.  Because  in  the  peculiar  and  common  or  lining  mem- 
brane of  these  vessels  there  is  no  cellular  texture. 

Properties  of  the  Vascular  System  with  Red  Blood. 
1.  Physical  Properties. 

Q.  What  physical  property  do  the  arteries  possess  in 
an  eminent  degree? 

t/#.  Elasticity,  and  this  property  distinguishes  them  prin- 
cipally from  the  veins. 

Q.  What  tubes  in  the  body  are  kept  open  by  this  elas- 
ticity ? 

«#.   The  arteries,  the  trachea,  the  meatus  auditorius  of 


VASCULAR    SYSTEM.  115 

the  foetus.  All  the  other  canals  approximate  their  inner- 
surface,  and  are  closed  when  their  distending  fluids  or 
contents  are  taken  away. 

Q.  How  does  a  flattened,  pressed,  or  bent  artery  reco- 
ver its  calibre  and  form  ? 

«#.  By  its  elasticity. 

Q.  What  do  you  mean  by  the  locomotion  of  an  artery  ? 

«#.  It  is  the  rising  of  an  artery,  and  the  straitening  of 
its  tube,  particularly  at  the  curves,  when  penetrated  by 
blood  or  injection,  and  its  return  to  the  natural  state  after- 
wards. This  is  principally  owing  to  the  elasticity  of  the 
arteries;  veins  manifest  no  such  properties. 

Q.  On  what  does  this  arterial  locomotion  depend? 

«#.  To  it  three  circumstances  are  essential ;  an  impel- 
ling power  as  that  of  the  heart,  the  tortuosities  in  the  ves- 
sels to  be  strained  by  the  blood  impelled,  and  firm  elastic 
coats. 

Q.  Can  you  distinguish  between  arterial  elasticity  and 
contractility  ? 

A.  Elasticity  is  a  physical  property,  contractility  an 
inherent  textural  one :  elasticity  presupposes  compression ; 
contractility  presupposes  the  absence  of  distending  con- 
tents: elasticity  is  quick  and  sudden  in  its  commencement 
and  termination ;  contractility  is  slow  with  a  permanent 
tendency  to  contract:  contractility  presumes  extensibility; 
elasticity  does  not. 

2.  Properties  of  Texture. 

Q.   How  do  the  arteries  manifest  extensibility  ? 
«#.   In  two  ways;  in  their  diameter  and  in  their  length, 
The  longitudinal  extensibility  is  greatest. 


116  VASCULAR    SYSTEM. 

Q.  On  what  structures  do  these  two  kinds  of.  extensi- 
bility depend? 

•ft.  That  of  the  diameter  depends  on  the  circular  fibres 
of  the  peculiar  membranes;  the  longitudinal  on  the  exten- 
sibility of  the  common  lining  membrane  and  its  folds,  for 
there  are  no  longitudinal  fibres  in  either  coat. 

Q.  What  results  from  the  limited  extensibility  of  the 
peculiar  or  fibrous  coat  of  the  arteries? 

•ft.  Its  rupture  in  aneurism.  The  more  slowly  the  dis- 
tention  of  the  peculiar  coat  is  made,  the  greater  the  extent 
to  which  it  may  be  carried. 

Q.   How  is  arterial  contractility  to  be  divided? 

•ft.   Lake  extensibility,  it  is  transverse  and  longitudinal. 

Q.   Give  instances  of  transverse,  arterial  contractility. 

A.  The  union  and  closure  of  the  umbilical  artery  and 
ductus  arteriosus;  the  emptying  of  an  artery  between  two 
ligatures;  the  closure  of  a  tied  artery  from  the  ligature  up 
to  the  first  branch  given  off;  and  the  diminution  of  the 
calibre  of  arteries  in  profuse  haemorrhage. 

Q.  How  do  you  account  for  a  small  and  large  pulse? 

•ft.  The  contraction  of  the  artery  when  empty  consti- 
tutes the  small  pulse,  and  the  expansion  when  full  of  blood 
the  large  one. 

Q.  Are  contractility  and  irritability  the  same? 

•ft.  They  are  entirely  different;  for  contractility  is  a 
property  of  texture,  irritability  is  a  vital  property.  Con- 
tractility continues  for  a  long  time  after  death,  irritability 
soon  disappears;  contractility  results  from  the  absence  of 
extension,  irritability  is  the  result  of  stimulus  applied. 

Q.  What  important  consideration  do  you  infer  from 
this  distinction? 

•ft.   The  superiority  of  that  system   should  be  well  re- 


VASCULAR    SYSTEM.  117 

collected,  which  recognises  the  marked  difference  between 
vital  and  textural  properties. 

Q.  Give  an  example  of  longitudinal  arterial  contrac- 
tility. 

Jl.  When  an  artery  is  cut  across  it  retracts. 

Q.  In  what  surgical  operation  is  this  kind  of  contrac- 
tility conspicuous? 

Ji.  The  retraction  of  the  spermatic  artery  is  remarkable 
when  the  cord  is  cut  in  extirpation  of  the  testicle. 

Q.  How  is  this  contractility  of  the  artery  to  be  over- 
come? 

Ji.  Tie  the  artery  before  the  vas  deferens  is  cut;  and 
then  it  does  not  retract  within  the  ring. 

3.    Vital  Properties. 

Q.  Do  the  arteries  possess  animal  sensibility? 

Ji.  Experiments  frequently  and  variously  made  prove 
that  they  do  not. 

Q.  What  nerves  supply  the  arteries? 

«/?.  The  nerves  of  organic  life. 

Q.  Is  animal  contractility  a  property  of  the  arteries? 

•ft.  Experiments  made  on  the  brain  and  spinal  marrow 
with  a  view  to  ascertain  this  point  prove,  that  injuries  of 
these  organs,  while  they  excite  the  animal  contractility 
into  convulsive  action,  do  not  influence  the  arteries  at  all: 
even  galvanism  failed  to  do  so. 

Q.  What  medical  doctrine  do  these  experiments  con 
tradict? 

«/?.  The  doctrine  of  the  influence  of  the  brain  on  the 
arteries. 


118  VASCULAR    SYSTEM.     ' 

Q.  Do  the  arteries  manifest  sensible  organic  contrac- 
tility? 

Ji.  They  do  not;  irritation,  in  whatever  way  applied, 
cannot  excite  it.  Contractility  of  texture  has  been  mis- 
taken for  sensible  organic  contractility. 

Q.   Repeat  the  organic  vital  forces  of  the  organs. 

«/?.  Sensible  organic  contractility;  insensible  organic 
contractility  and  organic  sensibility. 

Q.  Do  the  arteries  exercise  the  two  last  properties  in 
an  eminent  degree  ? 

Ji.  Only  to  obey  the  requisitions  of  nutrition;  hence 
these  vessels  are  little  liable  to  disease. 

Q.  What  is  liable  to  be  mistaken  for  inflammation  in  the. 
arteries? 

t/#.  A  redness  which  spontaneously  appears  in  them, 
particularly  in  the  cerebral  arteries,  after  death. 

.  Q.  What  would  be  the  consequence  if  the  arteries  were 
equally  liable  with  other  parts  to  disease? 

«#.  Inevitable  destruction  to  the  life  of  the  part,  and  in 
very  many  cases  general  death. 

Q.  Are  the  arteries  active  or  passive  in  this? 

*#.  From  th'e  absence  of  sensible  organic  contractility  it 
may  be  supposed  they  are  passive. 

Q.  Can  you  assign  reasons  for  believing  in  the  activity 
of  the  heart,  and  the  passive  state  of  the  arteries  in  circu- 
lating the  red  blood? 

*#.  These  reasons  are,  the  entire  difference  in  the  vital 
forces  of  the  heart  and  arteries:  affections  of  the  arteries 
do  not  disorder  the  pulse,  but  diseases  of  the  heart  do:  the 
artery  always  ceases  to  beat  below  a  ligature,  except  by 
anastomosis,  and  this  pulsation  is  from  the  heart  through 


VASCULAR    SYSTEM.  119 

the  anastomosing  branches:  cut  off  a  dead  man's  arm,  in- 
sert a  tube  in  the  brachial  artery,  place  the  other  end  of  the 
tube  in  the  carotid  artery  of  a  dog,  and  the  artery  in  the 
wrist  will  be  felt:  no  animal  has  arterial  pulsations  except 
those  with  hearts,  or  with  a  vascular  arrangement  giving 
an  impulse  as  the  heart  does:  lastly,  the  fatal  consequences 
of  independent  arterial  action  must  be  at  'once  evident. 

Q.  Where  does  the  power  of  the  heart  over  the  blood 
cease? 

Jl.  In  the  capillaries,  where  it  changes  from  red  to  black 
blood;  it  diminishes  sooner,  but  is  lost  there. 

Q.  With  what  textures  should  the  arteries  be  classed  ? 

•ft.  With  the  cartilaginous,  fibro-cartilaginous,  and 
fibrous  textures. 

Q.  What  moves  the  blood  in  the  capillaries? 

J3..  The  branches  are  so  minute  that  insensible  organic 
contractility  or  tonicity  is  sufficient  to  move  it. 

Q.  What  are  the  causes  chiefly  affecting  the  pulse? 

«#.  The  increase  of  the  sensible  organic  contractility  of 
the  heart ;  alterations  in  the  quality  of  the  blood  render- 
ing it  more  or  less  irritating  to  the  heart;  obstructions  in 
the  capillary  system;  all  these  produce  variations  in  the 
conditions  of  the  pulse. 

Q.  Are  the  sympathies  of  the  arterial  texture  numer- 
ous or  active? 

*ft.  The  obscurity  of  arterial  vital  properties  would 
answer  negatively.  ,  , 

Q.  How  do  the  vital  properties  of  organs  generally  in- 
fluence sympathy? 

Jl.  Sympathies  depend  on  vital  properties;  mechanical 
or  textural  properties  have  capacity  neither  to  radiate  nor 
receive  sympathetic  impressions. 


120  VASCULAR    SYSTEM. 

Q.  How  is  the  pulse  sympathetically  affected  ? 
«/?.   Always  through  the  heart. 

Of  the  Vascular  System  of  Red  Blood  in  different 

tfges. 

Q.  How  does  the  foramen  ovale  close? 

•ft.  By  the  gradual  approach  of  the  concave  surfaces  of 
the  two  crescentic  productions  forming  the  foramen  ovale, 
and  which  unite  and  decussate  at  birth,  closing  the  aper- 
ture. 

Q.  What  closes  the  ductus  arteriosus? 

t/?.  It  closes  as  the  pulmonary  artery  dilates. 

Q.  Is  there  red  and  black  blood  in  the  foetus,  as  in  in- 
dependent life? 

.#.  There  is  not;  all  the  foetal  blood  is  black. 

Q.  What  investigations  have  proved  the  black  colour  of 
the  foetal  blood? 

«#.  Animals  have  been  opened,  and  the  blood  of  the 
young  examined,  and  it  has  proved  to  be  black :  the  blood 
of  the  umbilical  arteries  is  black;  the  blood  of  the  foetus 
dead  in  the  mother  is  always  black ;  this  last  is  a  delusive 
circumstance. 

Q.  Does  it  follow  that  the  venous  blood  of  the  adult, 
and  black  blood  of  the  foetus  are  similar  in  qualities,  be- 
cause they  are  so  in  colour? 

.#.  It  does  not  thus  obtain.  Foetal  blood  is  unctuous  in 
its  feel;  it  does  not  coagulate  in  the  dead  body;  it  has  no 
fibrin;  it  does  not  take  the  vermilion  colour  from  the 
air;  it  has  no  phosphoric  salts. 

Q.   How  did  Sabatier  divide  the  mass  of  foetal  blood? 

«#.  In  two  circulations;  the  first  is  thus  laid  down: — 


VASCULAR    SYSTEM.  121 

The  blood  of  the  capillaries  of  the  inferior  extremities  of 
the  abdomen  and  umbilical  cord,  instead  of  going  from  the 
inferior  cava  to  the  right  auricle,  passes  to  the  left  auricle 
through  the  foramen  ovale,  and  thence  through  the  left , 
ventricle  into  the  carotids  and  head. 

Q.  Give  Sabatier's  second  division  of  the  foetal  circu- 
lation. 

./?.  It  is  that  the  blood  returning  from  the  head,  passes 
along  the  right  auricle,  ventricle,  and  pulmonary  artery, 
through  the  ductus  arteriosus  into  the  aorta  descendens, 
thence  into  the  capillary  system  of  the  abdomen  and  ex- 
tremities, and  partly  to  the  umbilical  arteries.  So  that 
there  are  two  circulations  in  the  foetus,  with  different 
origins,  trunks,  organs  of  impulse  and  terminations. 

Q.  In  this  system  of  Sabatier,  what  part  of  the  heart 
impels  the  blood  to  the  upper  and  lower  parts  of  the 
body? 

«#.  The  left  ventricle  propels  it  to  the  head;  the  right 
ventricle  to  the  lower  parts  of  the  body.  By  the  gradual 
closure  of  the  foramen  ovale  and  ductus  arteriosus,  the 
blood  takes  its  channels  for  life;  the  change  is  not  a  sud- 
den one. 

Q.   Is  the  arterial  system  early  developed? 

*#.  Of  course  it  is,  as  it  conveys  nutriment ;  but  the 
texture  is  soft,  yielding,  apparently  homogeneous.  The 
arterial  strengthens  as  the  heart  increases  in  vigour. 

Q.  What  changes  take  place  at  birth? 

«#.  In  the  red  blood  system,  two  changes  take  place ; 
the  one  is  mechanical,  the  other  is  chemical. 

Q.   What  are  these  mechanical  and  chemical  changes? 

«#.  The  mechanical  'are  the  closures  of  the  foramen 
16 


122  VASCULAR    SYSTEM. 

ovale  and  ductus  arteriosus;  the  chemical  change  is  the 
action  of  the  air  on  the  blood  in  the  lungs. 

Q.  How  does  respiration  commence  at  birth? 

«#.  In  consequence  of  a  general  excitement  produced  on 
all  the  moving  parts  from  external  impression  at  birth; 
perhaps  the  intercostals  and  diaphragm  are  set  in  motion 
instinctively. 

Q.  Are  you  correct  in  applying  the  term  instinct  in 
this  case? 

<A.  Yes;  for  various  examples  of  these  instinctive  ac- 
tions at  birth  can  be  presented.  Observe,  the  infant  pre- 
pares it  mouth  for  sucking;  animals  seek  the  teats  of  the 
mother;  gallinaceous  animals  look  for  grain,  &c.  to  nou- 
rish them. 

Q.  But  as  the  ductus  arteriosus  is  not  entirely  closed 
at  birth,  how  is  it  that  blood  does  not  pass  through  it? 

Ji.  It  is  accounted  for  in  two  ways;  the  capillaries  of 
the  lungs  invite  blood  through  the  pulmonary  artery,  and 
the  vital  forces  of  the  duct  itself  are  offended  by  blood 
which  is  not  placental;  thus  the  blood  goes  on  to  the 
lungs. 

Q.   How  is  the,  foramen  ovale  closed? 

«#.  When  the  blood  passes  from  the  pulmonary  veins 
into  the  left  auricle,  one  valve  of  the  foramen  is  pressed 
on  the  opening;  and  when  the  blood  comes  from  the  cavas 
into  the  right  auricle,  the  two  valves  are  completely  united, 
and  kept  so  till  union  permanently  takes  place. 

Q.  Can  the  foramen  ovale  remain  open  and  the  circula- 
tion go  on? 

*#.  It  can.  Bichat  has  repeatedly  seen  it;  for,  though 
open,  the  auricular  contraction  so  throws  the  valves  of  the 


VASCULAR    SYSTEM.  123 

foramen  into  contact,  as  to  close  it.  Again,  the  vital  forces 
of  the  left  auricle  may,  after  birth,  reject  black  venous 
blood;  this  is  the  elective  operation  of  the  vital  forces  of 
the  different  organs. 

Q.  You  have  stated  the  great  development  of  the  cere- 
bral arterial  system  in  infancy,  where  does  it  predominate 
at  puberty? 

A.  In  the  genital  organs  and  the  lungs. 

Q.  Where  is  vitality  most  active  in  adult  life? 

«#.  In  the  viscera  of  the  abdomen. 

Q,   How  many  kinds  of  bodily  growth  are  there? 

t#.  Growth  in  height,  and  thickness;  the  first  ends 
about  the  eighteenth  year,  the  second  continues  till  the 
fiftieth  year.  When  the  growth  in  thickness  ceases,  the 
calibres  of  the  arteries  no  longer  increases,  and  the  arte- 
rial development  has  no  local  preponderance. 

Q.  What  takes  place  in  the  arterial  system  of  old  age? 

JL.  The  blood  is  sent  with  diminished  force  to  the  small 
arteries;  they  gradually  close  and  are  obliterated. 

Q.  What  are  the  two  great  offices  of  the  circulation  of 
red  blood? 

«#*  To  impart  nutrition,  and  excite  the  organs  by  the 
arterial  motion. 

Q.  -Under  what  circumstances  are  the  arteries  acci- 
dentally developed? 

•#.  When  their  natural  course  is  obstructed ;  in  tumours; 
in  pregnancy.  Painful  tumours,  or  those  in  which  there 
is  an  exalted  animal  sensibility,  produce  this  development 
more  than  indolent  tumours. 

Q.  Does  Beclard  believe  that  the  arteries  do  not  possess 
sensible  organic  contractility? 


124  VASCULAR    SYSTEM. 

A.  He  is  of  opinion,  with  several  experimenters  sub- 
sequent to  Bichat,  that  they  do  exercise  that  vital  property. 

Q.  Is  this  sensible  organic  contractility  most  conspi- 
cuous in  the  large  or  small  arteries? 

*#.  In  the  smaller  ones,  because  of  the  great  nervous 
power  distributed  to  them. 

Q.  Why  do  you  think  that  the  arteries  aid  the  flow  of 
blood? 

•/?.  Because  the  flow  from  an  artery  is  constant;  if  it 
were  dependent  on  the  heart  alone,  the  blood  would  flow 
only  when  the  ventricle  contracted. 

Q.  Why  do  you  suppose  the  arteries  to  be  self-developed  ? 

«/?.  Because  vessels  exist  before  the  heart  does. 

Q.  Which  arterial  coat  is  most  liable  to  inflammation  ? 

Ji.  The  internal;  in  abdominal  and  thoracic  inflamma- 
tion, the  lining  membrane  of  the  aorta  is  found  red  and 
inflamed. 

Q.  Name  the  organic  alterations  of  the  arteries. 

«/?.  Inflammation,  aneurisms,  ossification,  cartilaginous 
transformation.  Ossification  frequently  brings  on  the  gan- 
grene of  old  persons. 


PATHOLOGY    OF    THE    VASCULAR    SYSTEM   WITH    RED 
BLOOD. 

Q.  To  what  diseases  are  the  arteries  liable  ? 

«#.  The  diseases  of  the  arteries  are  few.  They  are  in- 
flammation of  the  lining  membrane,  dilatation  of  the  ar- 
tery without  lesion,  contractions  of  the  arteries,  ossifica- 
tion, and  aneurism. 


VASCULAR    SYSTEM.  125 

Q.  Can  you  give  a  remarkable  fact  illustrating  the  in- 
disposition of  the  arteries  to  disease? 

«#.  This  is  one;  that  they  are  so  constantly  found  unin- 
jured while  all  the  surrounding  parts  are  destroyed. 

Q.   What  appearances  during  life  and  after  death  indi- 
cate inflammation  of  the  lining  membrane  of  the  arteries? 
*ft.   There  are  no  conclusive  symptoms  during  life;  and 
after  death   the  membrane  is  of  a  high  red  colour,  some- 
what thickened,  and  is  said  to  be  more  brittle. 

Q.  Where  do  you  see  dilatation  of  the  arteries  without 
lesion  ? 

«#.  It  has  been  seen  general  and  partial ;  the  coats  thick- 
en in  proportion  to  the  increase  of  the  size  of  the  artery. 

Q.  What  do  you  remark  of  the  contraction  of  the  arteries? 

t#.  It  is  also  general  or  partial.  The  first  arises  when 
the  vital  forces,  general  and  arterial,  are  much  diminish- 
ed; the  partial  is  seen  in  the  large  arterial  trunks. 

Q.   What  coat  is  most  liable  to  ossification? 

«#.   The  internal  membrane. 

Q.  At  what  age  does  this  ossification  occur? 

A.  Principally  in  the  aged. 

Q.  How  does  it  affect  the  pulse? 

«#.  It  renders  it  intermitting  and  irregular. 

Q.  Where  is  aneurism  oftenest  seen  ? 

«/2.  About  the  curvature  of  the  aorta ;  next  to  that  in  the 
abdominal  aorta. 

Q.  What  is  a  true  aneurism  ? 

•fl.  An  arterial  dilatation,  where  the  external  coat  is  un- 
ruptured,  although  the  middle  and  internal  may  be  burst. 

Q.  Define  a  false  aneurism. 

«#.  It  is  a  collection  of  blood  in  the  surrounding  cellu- 
lar texture  from  rupture  of  the  arterial  coats. 


126  VASCULAR    SYSTEM. 


MI.  VASCULAR  SYSTEM  WITH  BLACK  BLOOD. 

Situation,  Forms,  Division,  and  General  Arrange- 
ment. 

Q.   How  is  this  system  divided? 

t#.  Into  two  distinct  ones.  The  general  black  blood 
system,  and  the  black  blood  system  of  the  abdomen. 

Q.  What  proof  is  there  that  blood  is  not  formed  in  the 
general  capillary  system  ? 

*ft.  The  fact  that  no  veins  arise  from  parts  where  arte- 
ries are  not  sent. 

Q.   What  are  the  two  orders  of  veins? 

«/2.  Those  which  accompany  the  arteries,  and  those 
which  are  superficial,  sub-cutaneous. 

Q.  Where  do  the  veins  originate?    . 

«#.   From  the  general  capillary  system. 

Q.  Is  the  arterial  system  or  the  venous  most  capa- 
cious? 

t/2.  The  venous  is  much  more  capacious  than  the  arte- 
rial; there  is  no  fixed  disproportion. 

Q.  On  what  does  the  continuance  of  the  circulation  de- 
pend? 

A.  On  a  due  relation  between  the  capacity  of  the  sys- 
tems of  red  and  black  blood,  and  also  between  the  velo- 
city with  which  the  blood  is  propelled;  and  on  a  similar 
relation  between  the  origins,  agents  of  impulse,  and  ter- 
minations of  the  two  circulations. 

Q.  Which  side  of  the  heart  contains  most  blood  after 
death,  and  what  is  the  reason  ? 


VASCULAR    SYSTEM.  127 

^.  The  black  blood  side  of  the  heart;  and  the  reason  is 
that  the  circulation  ordinarily  stops  first  in  the  lungs,  and 
the  blood  is  by  this  pulmonary  obstruction,  collected  in 
the  right  side  of  the  heart. 

Q.  Why  is  there  weakness  of  parietes,  slowness  of  mo- 
tion, and  great  capacity  in  the  veins? 

«#.  The  parietes  are  comparatively  weak,  because  the 
veins  have  little  impulse  to  support;  the  velocity  is  not  so 
great  as  in  the  arteries,  because  the  force  of  the  heart  is  so 
little  felt  in  the  veins ;  the  capacity  is  great  in  the  veins 
that  they  may  bear  accumulations  from  gravity  and  other 
causes  with  safety. 

Q.  What  is  the  result  of  a  diminution  of  the  velocity 
of  the  blood  in  the  veins? 

«#.  It  increases  the  capacity  of  the  veins;  hence  the  dif- 
ference in  the  capacity  of  the  veins  of  the  inferior  and  su- 
perior extremities. 

Q.  What  is  the  principal  point  of  difference  in  the 
branches  of  the  veins  and  arteries? 

«#.  The  venous  are  much  less  tortuous,  and  hence  there 
is  no  locomotion  in  them. 

Q.  Where  are  the  ramifications  and  small  branches 
of  the  veins  usually  found? 

Jl.  The  ramifications  form  a  constituent  part  of  the  in- 
terior of  an  organ:  the  branches  lie  in  the  interstices, 
lobes  and  circumvolutions  of  the  organs. 

Q.  Why  are  the  large  arterial  and  venous  trunks  deep- 
seated  ? 

<fl.   To  preserve  them  from  injury. 

Q.  Considering  the  venous  system  as  a  whole,  what 
three  trunks  compose  it? 


128  VASCULAR     SYSTEM. 

«tf.  The  cava  superior,  the  cava  inferior,  and  the  coro- 
nary vein. 

Q.  What  difference  is  there  between  the  communica-4 
tions  of  the  arteries  and  of  the  veins? 

«/?.  The  venous  are  much  more  numerous  than  the  ar- 
terial; the  first  form  reticular  anastomoses,  such  as  are  not 
seen  in  the  latter. 

Q.  How  do  you  explain  the  continuance  of  the  venous 
circulation,  when  the  sub-cutaneous  veins  are  tied  or  other- 
wise obstructed  ? 

•#.  The  free  communications  between  the  superficial 
and  deep-seated  veins  account  for  it. 

Q.  Name  one  great  distinctive  mark  between  the  red 
and  black  blood  circulation? 

t/?.  The  influence  of  gravity  in  the  venous  circulation. 
Q.  What  arrangement  is  particularly  destined  to  coun- 
teract this  gravity  ? 

.#.  The  valves  of  the  veins. 
Q.  Why  is  gravity  so  powerful  in  the  veins? 
£.  Because  there  is  no  agent  of  impulse  at  the  origin 
of  the  black  blood  circulation  in  the  general  capillary  sys- 
tem. 

Q.  What  is  the  office  of  the  vena  azygos  ? 
«/?.  To  anastomose  between  the  superior  and  inferior 
cava.    This  free  anastomosis  precludes  the  idea  of  hepatic 
pressure  on  the  cava  producing  dropsy;  the  blood  finding 
its  way  through  the  azygos. 


VASCULAR    SYSTEM.  129 

Organization  of  the   Vascular  System   with   Black 
Blood. 

Q.  Of  what  is  the  peculiar  membrane  of  the  veins  com- 
posed? 

•#.  It  is  a  fine  layer  of  longitudinal  fibres. 

Q.  Where  is  this  membrane  most  conspicuous? 

•#.  In  those  veins  where  gravity  is  the  most  operative; 
and  in  the  superficial  veins  where  pressure  does  not  aid 
the  circulation  as  in  the  deep-seated  veins.  These  fibres 
can  be  better  seen  in  the  branches  than  in  the  trunks. 

Q.  What  is  Bichat's  opinion  of  this  membrane? 

«#.  That  it  is  a  texture  sui  generis. 

Q.  What  distinguishes  it  from  the  arterial  coat? 

*&.  The  absence  of  elasticity  and  brittleness;  its  soft- 
ness; its  great  extensibility  of  texture  j  and  the  longitudi- 
nal direction  of  its  fibres.  There  are  no  circular  fibres  in 
the  veins. 

Q.  Where  is  this  peculiar  membrane  found  wanting? 

•ft.  In  the  sinuses  of  the  dura  mater  there  is  neither  the 
cellular  coat  nor  fibrous  membrane;  the  venous  coats  there 
are  the  dura  mater  and  common  lining  venous  membrane. 

Q.  How  does  the  common  membrane  of  the  black  blood 
system  differ  from  that  lining  the  arteries? 

«#.  It  is  more  distensible,  it  is  more  delicate,  it  never 
ossifies.  Hence  you  do  not  see  ossification  in  the  right 
side  of  the  heart. 

Q.  Where  does  Beclard  say  the  venous  valves  are  most  < 
numerous? 

<ft.  In  the  superficial  veins;  in  those  of  the  inferior  ex- 
tremities. 

Q.  In  what  part  of  the  venous  system  are  there  no  valves? 

«#.  There  are  none  in  the  pulmonary  veins,  except  just 
17 


130  VASCULAR    SYSTEM. 

at  the  heart;  they  are  wanting  in  the  trunk  of  thecavaas- 
cendens,  in  the  emulgent  veins,  in  the  cerebral  sinuses. 
See  Horner,  Vol.  II.  p.  158. 

Q.   How  are  the  venous  fibres  best  exhibited? 

*#.  By  plunging  the  veins  into  boiling  water  or  concen- 
trated acids,  the  horny  hardening  contraction  takes  place, 
and  the  fibres  are  seen. 

Q.  What  distinguishes  the  venous  parietes  from  the 
arterial? 

.#.  The  penetration  of  cellular  texture  between  the 
fibres  of  the  peculiar  coat  of  the  veins,  into  the  common 
lining  membrane.  This  is  not  seen  in  the  arteries.  The 
cellular  coat  of  the  veins  is  peculiarly  filamentous. 

Q.  To  what  extent  do  exhalation  and  absorption  take 
place  in  the  veins? 

A.  Only  to  subserve  the  purposes  of  nutrition. 

Q.  Are  the  veins  as  abundantly  supplied  with  nerves 
as  the  arteries? 

«#.   They  are  not;  a  few  ganglionic  nerves  supply  them. 

Q.  What  induces  you  to  believe  that  the  nerves  have 
no  effect  on  the  contraction  of  the  left  side  of  the  heart? 

«/?.  The  fact  that  the  right  side  is  as  abundantly  sup- 
plied with  nerves  as  the  left.  We  would  therefore  sup- 
pose that  nervous  influence  does  not  confer  the  difference 
of  ventricular  power. 

Properties  of  the  Vascular  System  with  Black  Blood. 
1.  Properties  of  Texture. 

Q.  Are  the  veins  extensible? 

JL.  They  are,  but  in  a  transverse  direction;  the  arteries 
are  so  longitudinally. 

Q.  Have  not  recent  investigations  proved  that  the  veins 
are  extensible  longitudinally? 


VASCULAR    SYSTEM.  131 

•#.  They  have;  Puschett,  a  German,  has  seen  them  be- 
come tortuous  and  longer  in  disease. 

Q.  Are  the  veins  easily  or  frequently  ruptured  ? 

•fl.  They  are;  for  example,  the  haemorrhoidal,  the  ce- 
phalic; even  the  jugular  and  cava  veins  have  been  ruptur- 
ed. Call  to  mind  the  thin  parietes  of  the  cephalic  veins. 

Q.  Is  the  venous  texture  contractile? 

•/?.  Evidently  so.  The  contractility  is  slight  in  the  lon- 
gitudinal, much  greater  in  the  transverse  direction. 

Q.  What  circumstances  affect  this  contractility? 

Jl.  Seasons  of  the  year,  posture  of  the  body,  cold  or 
hot  applications,  and  period  of  life. 

2.    Vital  Properties. 

Q.  Have  the  veins  animal  sensibility  and  contractility  ? 

•fl.  Bichat  says  that  experiments  prove  them  destitute 
of  these  properties. 

Q.  Does  notBeclard  allow  the  veins  vital  contractility? 

A.  Yes;  various  experiments,  he  says,  prove  that  the 
veins  in  the  living,  contract  in  a  manner  not  seen  in  dead 
bodies;  hence  it  is  a  vital,  not  a  textural  contractility. 

Q.  Do  the  veins  possess  sensible  organic  contractility  ? 

«/?.  They  do  not;  for  in  disease  the  veins  manifest  none 
of  those  evidences  of  increased  sensible  organic  contrac- 
tility which  the  heart,  stomach,  or  bladder  give  out. 

Q.  What  light  does  disease  throw  on  the  predominant 
vital  forces  of  our  organs  ? 

«/2.  Diseases  exalt  those  that  are  predominant,  so  as  to 
show  those  that  prevail  in  the  different  organs  in  health. 

Q.   How  does  Bichat  account  for  the  venous  pulse  ? 

«#.   He  ascribes  it  to  a  reflux  of  blood  from  the  right 


132  VASCULAR    SYSTEM. 

side  of  the  heart,  in  consequence  of  pulmonary  obstruction, 
or  of  an  irregular  action  of  the  heart.  These  occasion  a 
psuedo-pulsation,  resulting  from  the  contractility  of  tex- 
ture, not  from  irritability. 

Q.  How  far  is  this  reflux  operative? 

•ft.  Rarely  beyond  the  great  trunks;  it  is  stopped  by 
the  valves.  Haller  said  it  extends  to  the  iliacs. 

Q.  Why  do  wounded  veins  inflame  and  unite  so  much 
more  speedily  than  arteries? 

•ft.  Because  the  tonic  vital  forces  are  greater  in  the  veins 
than  arteries,  because  the  action  of  the  arteries  may  pre- 
vent union,  and  perhaps  because  there  is  more  cellular  tex- 
ture in  the  veins  than  in  the  arteries. 

Q.  How  is  the  blood  moved  from  the  general  capilla- 
ries through  the  veins? 

•ft.  By  the  insensible  contractility  of  the  capillaries;  by 
an  absorbing  power  which  commences  in  the  venous  ra- 
mifications, and  extends  towards  the  venous  trunks. 

Q.  But  as  the  resistance  to  the  motion  of  the  blood  in 
the  veins  is  often  greater  than  the  impulse,  how  does  it 
get  forward? 

•ft.  By  various  aids;  by  anastomoses;  by  muscular  ac- 
tion and  pressure ;  by  assistance  from  the  pulsation  of  the 
neighbouring  arteries;  by  the  motion  of  certain  parts,  as 
the  elevation  and  depression  of  the  cerebral  mass;  by  the 
locomotion  of  other  organs,  as  the  gastric  ;  and  by  external 
frictions  and  motions.* 

Q.  Can  you  give  a  parallel  view  of  the  circulation  in 
the  arteries  and  veins? 

*  For  a  more  particular  account  of  the  forces,  by  which  the  blood 
is  made  to  circulate  in  the  veins,  see  Arnott's  Elements  of  Physics, 
American  Edition,  p.  446,  et  seq. 


VASCULAR    SYSTEM.  133 


In  the  arteries  there  is 

Pulsation, 

Rapid  flow  of  blood, 

Small  capacity  and 
thick  parietes, 

No  necessity  for  ac- 
cessory aid, 

Blood  flowing  per 
saltern, 

Very  little  arterial 
gravitation. 


In  the  veins  there  is 
No  pulsation, 
Slow  motion  of  the  blood, 
Great   capacity  and  thin 

parietes, 
Necessity    for    accessory 

aid, 
Uniform  flow  of  blood, 

Power  of  gravity  in  the 
veins. 


Q.  What  are  the  effects  from  an  organ  of  impulse  at  the 
origin  of  the  arteries? 

t#.  It  gives  uniformity  of  pulsation  or  motion  in  the 
arteries,  and  you  find  all  the  arteries  of  the  body  equally 
dilated  or  contracted  after  death. 

Q.  Now,  what  results  proceed  from  the  absence  of  an 
organ  of  impulse  at  the  capillary  origin  of  the  veins  ? 

t/tf.  The  blood  is  propelled  with  very  various  power  in 
different  parts  of  th6  body ;  and  there  is  great  variety  in 
the  states  of  fulness  or  contractions  of  different  veins  in  the 
several  parts  of  the  body. 

Development  of  the  Arterial  System  with  Black  Blood. 

Q.  Is  the  arterial  or  venous  system  most  developed  in 
foetal  life? 

w2.  The  arterial  much  more  so;  less  blood  returns  by 
the  veins,  because  of  the  quantity  exhausted  by  nutri- 
tion. 

Q.  What' veins  have  been  found  developed  before  the 
arteries? 

•#.  The  umbilico  mesenteric  in  the  chick. 


134  VASCULAR    SYSTEM. 

Q.   Why 'are  varices  rare  in  foetal  life? 

./?.  Because  the  venous  coats  are  very  strong  at  that 
period;  more  so  in  proportion  than  in  after  life. 

Q.  What  alterations  take  place  in  the  veins  of  old 
age? 

*#.  A  dilatation  of  their  parietes,  a  diminished  contrac- 
tility in  the  capillaries,  a  diminished  velocity  in  the  mass 
of  venous  blood  from  an  increased  capacity  in  the  veins. 

Q.  How  does  Bichat  account  for  the  quantity  of  blood 
in  old  age? 

«/?.  As  decomposition  prevails  over  nutrition  in  ad- 
vanced life,  and  the  veins  receive  the  decomposed  matter, 
they  contain  a  greater  quantity  of  blood. 

Q.   Where  are  varices  principally  found? 

A.  In  the  inferior  extremities  of  old  persons,  and  of 
pregnant  women;  the  causes  are  obvious. 

Q.  Why  are  the  veins  enlarged  in  cancer,  fungus,  &c.? 

A.  The  arterial  deposition  being  increased,  the  venous 
fulness  is  in  proportion  augmented. 

Q.  Why  is  the  capacity  of  the  veins  enlarged  in 
ascites? 

•ft.  Because  their  coats  have  lost  a  measure  of  their 
elasticity. 

Q.  What  would  be  the  effect  on  the  circulation,  if  the 
blood  went  from  the  ventricles  by  two  arterial  orifices? 

JL.  There  would  be  neither  unity  of  impulse,  uniformity 
of  course,  or  simultaneous  pulsation.  These  are  all  pre- 
served by  the  single  aortal  trunk. 

Of  the  Abdominal  System  with  Black  Blood. 
Q.  What  organs  supply  this  vena  portal  circulation? 


VASCULAR    SYSTEM.  135 

Jl.  Those  concerned  in  digestion. 

Q.  Name  those  organs  or  parts  which  do  not  pour  their 
blood  into  this  vena  portal  system. 

t/2.  The  kidneys,  ureters,  bladder,  genital  organs,  dia- 
phragm, and  abdominal  parietes,  do  not  empty  their  blood 
into  the  vena  portarum. 

Q.  Do  the  properties,  sympathies,  and  affections  of  this 
abdominal  venous  system  agree  with  the  general  venous 
system  ? 

J2.  They  do. 

Q.  What  membrane  is  peculiar  to  the  hepatic  portion? 

«/?.  That  which  is  termed  the  capsule  of  Glisson;  the 
use  of  which  is  unknown. 

Q.  What  proof  is  there  that  the  injection  of  air  into  the 
veins  is  not  fatal  by  impression  made  on  the  heart  ? 

•ft.  Because  injection  of  air  into  the  abdominal  system 
with  black  blood  is  not  fatal,  and  yet  the  air  must  reach 
the  heart. 

Q.  How  then  does  air  prove  fatal  when  thrown  into 
the  blood-vessels? 

t/2.  By  its  action  on  the  brain.  In  the  case  alluded  to 
in  the  last  question,  the  air  becomes  so  united,  diluted, 
&c.  before  any  of  it  reaches  the  brain  that  its  power  is  lost. 

Q.  How  does  the  common  lining  membrane  of  this  ab- 
dominal system,  differ  from  that  of  the  general  venous 
system  ? 

«#.  It  has  no  valves;  these  are  unnecessary,  because  the 
course  of  the  blood  is  short.  There  is  no  agent  of  impulse 
in  the  middle  of  this  system,  as  you  see  in  the  right  side 
of  the  heart;  the  effect  of  such  an  agent  might  occasion  a 
reflux  as  the  action  of  the  right  ventricle  does. 

Q.  Is  the  course  of  the  blood  uniform  through  the  liver? 


136  VASCULAR    SYSTEM. 

.#.  The  want  of  impulse,  the  solidity  of  the  liver,  the 
absence  of  hepatic  dilatation  and  contraction,  all  render 
the  circulation  much  more  uniform  than  it  is  in  the  lungs 
where  the  black  blood  system  terminates. 

Q.  Do  the  coats  of  the  abdominal  veins  differ  in  strength 
from  those  of  the  general  circulation? 

*fl.  They  are  of  the  same  firmness. 

Q.  What  aids  the  circulation  of  blood  through  the  ab- 
dominal veins? 

«#.  The  movements  of  the  diaphragm  and  abdominal 
muscles;  the  motion,  dilatation  and  contraction  of  the 
hollow  viscera;  the  constant  motion  of  the  intestines.  You 
will  observe  that  in  the  haemorrhoidal  veins,  that  not 
having  these  aids  in  their  circulation,  there  are  very  fre- 
quent varicose  enlargements. 

Q.  What  induces  the  belief  that  the  liver  performs  some 
very  important  though  unknown  office  in  the  system? 

A.  Thev  great  disproportion  between  the  size  of  the 
liver  and  its  excretories  and  reservoirs,  and  that  of  the 
kidneys,  salivary  glands,  pancreas  and  their  emunctories; 
the  greater  flow  of  secreted  fluids  from  the  test  mentioned 
viscera  than  from  the  liver,  although  that  is  in  size  greater 
than  all  of  them  collectively  taken;  the  fact  that  the  liver 
is  universally  found  in  animals;  the  early  foetal  develope- 
ment  of  the  viscus,  its  being  coeval  with  the  heart  and 
brain;  the  great  influence  the  passions  have  over  it;  the 
conspicuous  part  it  performs  in  the  diseases  of  the  ceco- 
nomy;  the  influence  of  the  liver  on  temperaments;  its 
frequent  organic  diseases;  all  these  impose  the  belief  sug- 
gested in  the  question. 

Q.  Does  the  liver  effectuate  any  change  on  the  vena 
portal  blood? 


VASCULAR    SYSTEM.  137 

v?.  Experiment  proves  that  it  does  not. 

Q.  What  are  the  evidences  that  bile  is  exclusively 
formed  by  the  vena  portal  blood  ? 

A.  This  remains  but  a  plausible  hypothesis;  there  is 
no  positive  proof  of  the  fact.  Bichat  thinks  that  both  the 
vena  portal  blood  and  that  of  the  hepatic  artery  concur  to 
form  the  bile. 

Q.  Does  the  blood  of  the  venaportarum  differ  from  the 
black  blood  in  the  general  system? 

«#.  It  has  been  so  supposed,  but  the  reasons  are  exceed- 
ingly doubtful  in  their  character. 

Q.  Does  the  slow  motion  of  the  blood  in  the  vena  por- 
tarum  favour  the  biliary  secretion? 

£.  As  this  sluggish  circulation  does  not  appear  in  other 
organs,  there  is  no  reason  to  believe  it  necessary  or  con- 
ducive to  the  hepatic  secretion. 

Q.  What  proof  is  there  that  the  spleen  does  not  send 
matter  essential  to  the  formation  of  bile? 

.#.  Because,  where  the  spleen  is  wanting,  or  removed, 
bile  has  been  formed  in  the  usual  manner. 

Q.  Is  the  flow  of  bile  into  the  duodenum  constant? 

A.  The  hepatic  flows  constantly;  the  cystic  only  during 
intestinal  digestion. 

Q.  Does  Bichat  suppose  that  bile  exists  in  the  stomach? 

<ft.  From  experiments  made  on  animals  he  believes  that 
bile  is  always  in  the  human  stomach;  and  that  it  is  hepa- 
tic, not  cystic  bile,  which  is  found  there. 

Q.  At  what  stage  of  life  does  the  liver  receive  most 
blood? 

*ft.  In  the  foetal  period. 

Q.  What  difference  does  birth  make  in  the  circulation 
of  the  liver? 

18 


138  VASCULAR    SYSTEM. 

•fl.  But  one  kind  of  blood  enters,  and  less  of  that;  an 
interruption  to  all  communication  between  the  general 
and  abdominal  black  blood  system  takes  place,  and  a 
diminished  size  of  the  liver. 

Q.  At  what  period  of  life  is  the  circulation  in  the  ab- 
dominal system  of  black  blood  most  active? 

<fl.  From  the  thirtieth  to  the  fortieth  year;  and  it  is  at 
that  period  that  diseases  of  the  abdominal  system  ap- 
pear. 

Q.  What  are  these  diseases? 

*ft.   Haemorrhoidal  affections,  and  melancholia. 

Q.   Do  you  ever  see  ossification  in  this  system? 

rf.   Never. 


PATHOLOGY  OF  THE  VASCULAR   SYSTEM  WITH   BLACK 
BLOOD. 

Q.  What  are  the  diseases  of  the  veins  ? 

*#.  They  are  few,  and  imperfectly  understood.  There 
is  inflammation  or  phlebitis;  dilatation;  contraction;  and 
concretions  in  the  veins. 

Q.  Name  a  remarkable  pathological  contrast  in  the  state 
of  the  arteries  and  veins  in  fever. 

Ji.  While  the  arteries  are  in  tumultuous  action,  the 
veins  are  quiet  as  in  health. 

Q.  What  are  the  causes  of  inflammation  of  the  veins? 

*#.  The  cause  is  sometimes  unknown;  usually  it  arises 
either  from  wounds  of  the  veins,  or  from  ligatures,  as  in 
varicose  veins  after  an  operation,  or  from  inflammation  of 
surrounding  tissues,  or  from  a  varicose  state. 


VASCULAR    SYSTEM.  139 

Q.  What  are  the  appearances  of  an  inflamed  vein  on 
dissection  ? 

t#.  There  is  some  redness  of  the  inner  coats,  with 
thickening  of  the  outer  tunics.  Pus  forms  on  the  exterior 
coats,  and  lymph  on  the  internal  coat  in  phlebitis. 

Q.  In  what  direction  does  venous  inflammation  ex- 
tend? 

ift.  In  general  between  the  orifice  or  puncture  and  the 
heart. 

Q.  How  are  venous  dilatations  divided? 

«/?.  Into  local  and  general;  and  into  those  of  the  gene- 
ral venous  and  those  of  the  vena  portal  system. 

Q.  What  are  these  dilatations  called  ? 

*&.  Varices  in  the  general  venous  system;  and  haemor- 
rhoids when  they  appear  in  the  vena  portal  system  near 
the  rectum. 

Q.  What  is  the  appearance  of  a  varix? 

,#.  It  is  a  blue  soft  tumour,  which  increases  in  propor- 
tion to  the  compression  between  it  and  the  heart. 

Q.  What  causes  a  varix? 

*#.  It  occurs  when  the  coats  of  the  vein  cannot  main- 
tain the  gravity  of  a  column  of  blood. 

Q.  Where  are  these  varices  most  frequent? 

*ft.  In  the  spermatic  veins,  and  those  of  the  inferior  ex- 
tremities. They  are  seldom  seen  in  the  superior  parts  of 
the  body.  I  have  seen  an  enormous  dilatation  of  the  left 
jugular  vein,  from  obstruction  to  the  passage  of  blood  from 
the  right  side  of  the  heart. 

Q.  How  many  kinds  of  hsemorrhoidal  dilatations  ? 

A.  Two;  one  with  rupture  of  the  venous  coats;  the 
other  without.  There  are  haemorrhoids  from  which  the 


140  VASCULAR    SYSTEM. 

blood  is  evacuated  externally ;  this  is  a  species  of  the  first 
form. 

Q.   What  is  an  aneurismal  varix? 

«#.  The  case  where  there  is  an  abnormal  direct  com- 
munication between  the  artery  and  vein. 

Q.   How  are  contractions  of  the  veins  induced? 

«#.  By  chronic  inflammation  and  thickening  of  the  ve- 
nous parietes. 

Q.  Where  are  venous  concretions  seen? 

«#.  They  have  been  seen  in  the  pelvic  veins,  about  the 
size  of  a  pea. 

Q.  What  great  difference  is  there  in  the  pathological 
tendencies  of  the  internal  membrane  of  the  veins  and  that 
of  the  arteries? 

•#.  The  venous  is  not  disposed  to  ossify,  the  arterial  is, 


CAPILLARY  SYSTEMS. 

Q.  What  are  the  two  capillary  systems? 

Jl.  The  general  capillary  system,  which  is  the  seat  of 
the  alteration  of  the  red  to  the  black  blood ;  and  the  pul- 
monary capillary  system  in  which  the  blood  is  converted 
from  black  to  red  blood. 

Q.  Whence  the  great  importance  of  these  capillary  sys- 
tems? 

Ji.  They  are  the  seats  of  the  most  important  functions, 
such  as  nutrition,  secretion,  digestion,  absorption,  exhala- 
tion; the  capillary  circulations  are  governed  by  peculiar 
laws;  their  tubes  are  the  seats  of  inflammation,  metastases; 
and  animal  heat  is  engendered  there. 

Q.  In  what  animals  are  these  systems  exclusively  the 
organs  of  circulation  ? 

i/2.   In  the  lowest  classes  of  animals. 

I.   GENERAL  CAPILLARY  SYSTEM. 

Q.   What  is  the  extent  of  this? 

t/f.  All  the  organs  are  composed  of  myriads  of  capilla- 
ries, intercommunicating  in  every  possible  way;  arterial 
and  venous  ramifications  pass  into  the  interstices  of  the 
organs;  the  organs  themselves  are  composed  of  capilla- 
ries. 

Q.  Do  yqu  say  that  the  capillaries  are  a  class  of  vessels 
distinct  from  the  blood-vessels? 

ei.  Not  only  so,  but  they  give  rise  to  the  exhalents  and 


142  CAPILLARY    SYSTEMS. 

absorbents.  The  capillary  systems  are  intermediate  be- 
tween the  arteries  and  veins.  Nutritive  matter  for  all  the 
organs  is  by  them  separated  from  the  blood. 

Q.  How  are  the  general  capillaries  divided? 

«#.  There  are  those  which  carry  red  blood ;  those  which 
convey  white  fluids;  and  those  giving  passage  to  both  red 
and  white  fluids. 

Q.  In  what  systems  do  the  capillaries  with  red  blood 
predominate? 

*#.  In  the  muscular  tissue,  in  the  spleen,  in  portions  of 
the  mucous  system,  as  the  pituitary  membrane. 

Q.  In  what  systems  do  the  blood  and  other  fluids  also 
circulate?. 

e#.  In  the  capillary  systems  of  the  osseous,  serous, 
some  of  the  fibrous,  the  dermoid,  and  glandular  tissues, 
besides  others. 

Q.   How  is  this  mixed  circulation  proved? 

«/#.  By  the  comparison  of  a  piece  of  healthy  serous 
membrane  in  health  and  the  same  in  a  state  of  inflamma- 
tion: by  injecting  the  capillary  system  of  the  serous  mem- 
branes it  exhibits  a  net-work  of  vessels  not  apparent  in  a 
natural  state:  the  appearance  of  the  inflamed  conjunctiva 
is  a  remarkable  illustration  of  the  question  proposed.  The 
proportions  of  the  red  and  white  capillaries  vary  in  dif- 
ferent textures;  there  are  fewer  red  capillaries  in  the  se- 
rous tissues,  while  in  the  dermoid  and  mucous  tissues  they 
preponderate  greatly. 

Q.  What  hypothesis  has  Bichat  connected  with  this  ? 

£.  That  there  may  be  a  set  of  empty  vessels,  which  in 
a  natural  state  do  not  convey  blood,  but  which  are  pre- 
pared to  receive  it  in  cases  of  emergency. 

Q.  What  organs  have  white  capillaries  exclusively? 


CAPILLARY    SYSTEMS.  143 

JL.  Tendons,  cartilages,  hair,  some  ligaments. 

Q.  How  do  you  prove  the  existence  of  any  capillaries 
in  these? 

./?.  Injections  and  disease  prove  it;  these  tissues  are 
really  vascular. 

Q.  On  what  does  the  number  of  capillaries  in  a  part_ 
depend  ? 

*fl.  It  depends  on  the  functions  they  perform.  Those 
having  few  capillaries,  such  as  cartilage,  have  only  nutri- 
tion to  support;  others  have  exhalation  and  absorption; 
and  others  again  have,  superadded  to  all  these,  secretions 
to  form. 

Q.  What  is  the  pathological  distinction  between  active 
and  passive  increased  secretion  and  exhalation? 

«/!?.  Preceding  the  active  there  is  an  increased  afflux  of 
blood;  in  the  passive  this  is  not  the  case. 

Q.  What  do  you  mean  by  an  active  secretion  or  exha- 
lation ? 

Jl.  One  attended  with  an  increase  of  the  vital  forces; 
in  the  passive  forms  there  is  a  diminution  of  these  forces. 

Q.   Give  a  definition  of  the  general  capillary  system? 

Jl.  It  is  a  general  net-work,  which  communicates  in 
every  organ,  and  from  one  organ  to  another;  forming  in 
this  way  free  communications  for  the  fluids  of  the  body 
from  head  to  foot. 

Q.  How  does  this  view  affect  the  usually  admitted  at- 
tributes of  the  cellular  texture  ? 

t/2.  It  has  been  thought  that  the  permeability  of  the 
body  depended  on  the  cellular  texture,  but  here  you  see 
it  ascribed  to  the  capillary  system. 

Q.  Do  the  capillary  vessels  conveying  red  and  white 
fluids  freely  communicate? 


144  CAPILLARY    SYSTEM?. 

A.  They  do  very  freely  wherever  they  are  met  with. 

Q.  What  is  the  pathology  of  haemorrhage? 

J2.  It  is  an  active  or  passive  exhalation  of  blood,  as 
the  case  may  be;  it  is  not  from  rupture  of  vessels. 

Q.  What  relation  does  this  general  capillary  system 
bear  to  the  arteries  and  veins? 

«/#.  It  is  a  general  reservoir,  into  which  arteries  pour 
red  blood,  and  from  which  the  veins  take  black  blood; 
from  which  also  the  exhalents  with  nutritive  and  other 
matters  pass;  the  excretions  arise  from  it;  the  secretory 
vessels  elaborate  their  fluids  from  the  blood  in  the  general 
capillary  system. 

Q.  What  proves  this  distinct  organization  or  continuity 
of  tubes  ? 

«/2.  The  continuity  from  the  arterial,  through  the  capil- 
lary, to  the  venous  system,  is  proved  by  the  fact  that  in- 
jections from  the  arteries  do  not  pass  into  the  cellular 
texture. 

Q.  What  effect  has  this  permeability  of  the  capillary 
system  on  the  appearances  of  parts  on  dissection? 

.#.  Before  death,  tonic  action  preserves  the  fluid  in  a 
precise  part;  hence  in  membranous  inflammation  the  red- 
ness. But  after  death,  these  fluids  obeying  gravity ,'J,he 
parts  lose  the  redness  which  indicates  inflammation,  and 
the  dissector  may  imagine  there  was  none.  Local  irrita- 
tion, which  fixed  blood  in  a  part  during  life  and  disease, 
disappearing  after  death,  the  blood  is  removed. 

Q.  Does  blood  disappear  equally  after  death  from  chro- 
nic as  from  acute  inflammation? 

•ft.  It  does  not;  in  chronic  it  is  more  fixed,  forming  al- 
most a  constituent  part  of  the  tissue. 


VAPILLART    SYSTEMS.  145 

Q.  Why  is  it,  that  while  the  capillary  tubes  are  free 
and  every  where  open,  the  blood  does  not  pass  into  all? 

A.  A  general  physiological  reply  may  serve,  viz.  that 
the  organic  sensibility  of  different  organs  admits  certain 
matters,  and  rejects  all  others.  Such  is  the  case  with  the 
trachea  and  lacteals,  and  many  others. 

Q.  How  then  is  there  an  occasional  increased  flow  of 
blood  to  a  part? 

«#.  Irritation  applied  to  that  part,  increases  the  organic 
sensibility,  and  thus  more  blood  appears  in,  or  is  invited 
to  it. 

Q.  What  is  the  great  difference  between  organized  and 
inert  tubes  or  vessels? 

*#.  The  vitality  of  the  organized,  and  the  inert  being 
under  the  influence  solely  of  mechanical  laws. 

Q.  Where  is  it  that  organic  sensibility  varies  most,  and 
thus  affects  the  course  of  the  blood? 

•/?.  This  takes  place  in  the  capillary  system ;  not  in  the 
large  vessels. 

Of  Inflammation. 

Q.  What  is  the  first  step  in  the  pathology  of  inflam- 
mation ? 

•#.  An  alteration  and  increase  of  the  organic  sensibility, 
in  consequence  of  an  irritant  to  the  part. 

Q.   How  is  this  local  irritation  produced? 

<fl.  By  direct  irritation,  or  by  organic  continuity,  or  by 
sympathy. 

Q.  What  is  the  second  step  in  the  process  of  inflam- 
mation? 

t#.  An  irritation  of  blood  by  the  increased  organic  sen- 
sibility, and  a  remora  of  blood  while  irritation  continues. 

19 


146  CAPILLARY    SYSTEMS, 

Q.   How  is  pain  produced  in  inflammation? 

Jl.  By  the  alteration  and  increase  of  organic  sensibility 
into  animal  sensibility,  which  last  is  perceived  by  the  brain. 
JThe  impression  of  the  blood  on  this  increased  organic  sen- 
sibility gives  pain. 

Q.  How  is  heat  evolved  in  inflammation  ? 
'  «#.  It  is  a  result  of  the  alteration  of  the  organic  vital 
forces. 

Q.  What  do  you  mean  by  a  greater  or  less  degree  of 
inflammation? 

«#.  An  indication  of  the  extent  in  the  increase  and  al- 
teration of  the  organic  sensibility.  ( 

Q.  You  speak  of  an  alteration  as  well  as  an  increase  of 
the  organic  sensibility,  will  you  explain  this? 

«/?.  By  a  simple  increase  of  this  organic  sensibility,  in- 
flammation is  produced;  by  an  alteration  of  the  sensibility 
the  inflammation  is  modified. 

Q.  How  do  the  fluids  become  putrid? 

Jl.  To  make  this  change  in  the  fluids,  a  previous  de- 
struction of  the  vital  forces  of  the  part  is  essential.  * 

Q.  How  do  local  affections  modify  fever? 

«/2.  Bichat  supposes  that  each  local  affection  has  its  ap- 
propriate general  fever. 

Q.  What  leads  to  different  terminations  in  inflammation? 

<&.  Changes  in  organic  sensibility;  reduction  of  animal 
sensibility;  exhaustion  of  organic  sensibility,  according  as 
it  ends  in  resolution,  suppuration,  scirrhus,  or  death. 

Q.  Why  is  the  agency  of  the  nerves  rejected  as  induc- 
ing inflammation? 

*#.  In  the  system  of  Bichat,  the  nerves  are  allowed  no 
control  over  organic  sensibility,  in  the  changes  of  which 
inflammation  consists. 


CAPILLARY    SYSTEMS.  147 

Q.  What  relations  do  the  black  and  red  blood  bear  to 
inflammation? 

•ft.  When  the  inflammation  is  active,  the  red  blood  is 
found  in  the  capillaries;  when  the  inflammation  is  passive, 
black  blood  is  in  them. 

Q.   In  what  tissues  is  inflammation  most  frequent? 

•ft.  In  those  tissues  where  there  are  the  greatest  num- 
ber of  capillaries,  such  as  the  mucous  and  serous.  It  at- 
tacks those  tissues  where  the  functions  of  the  capillaries 
are  most  diversified,  that  is,  where  nutrition,  secretion,  ex- 
halation and  absorption  exist.  Where  nutrition  is  only  in 
existence  in  the  capillaries  of  a  tissue,  inflammation  is 
comparatively  rare. 

Q.  What  accounts  for  the  different  aspects  of  inflam- 
mation in  the  various  tissues? 

•ft.  The  varieties  in  the  organic  sensibility  of  these  tis- 
sues. 

Q.   What  inflammation  prevails  in  the  cellular  texture? 

•ft.  The  phlegmonous  form. 

Q.  What  inflammation  is  most  common  in  the  skin  ? 

•ft.  The  erysipelatous. 

Q.  What  is  the  inflammation  observed  in  the  mucous 
tissue? 

•ft.  It  is  the  catarrhal. 

Q.  Do  the  fluids  formed  in  the  terminations  of  these 
inflammations  differ? 

«/?.  They  do.  The  pus  of  phlegmon  differs  from  that  of 
erysipelas.  There  is  no  resemblance  between  the  fluid  of 
catarrh,  and  the  flaky  fluids  from  the  serous  surfaces.  The 
fibrous  tissue  does  not  suppurate. 

Q.  Is  there  a  peculiarity  of  structure  in  the  capillaries 
of  the  various  organs? 


148  CAPILLARY    SYSTEMS. 

*#.  It  is  probable  that  they  partake  of  the  structure  of 
the  different  organs;  that  they  have  peculiar  organic  sen- 
sibility, and  insensible  organic  contractility,  and  conse- 
quently peculiar  diseases. 

Of  the.  Capillary  Circulation. 

Q.  What  are  the  features  of  this? 

.#.  Two  conspicuous  ones  invite  attention;  they  are  the 
motions  of  the  fluids,  and  the  alterations  they  undergo. 

Q.   What  are  these  fluids? 

•/!?.  The  blood,  which  is  known;  the  other  fluid  in  ca- 
pillary circulation  is  unknown. 

Q.  How  are  the  fluids  circulated  in  the  capillaries? 

&.  Not  by  the  heart;  but  the  fluids  coming  in  contact 
with  the  capillaries,  excite  through  their  organic  sensi- 
bility, the  insensible  organic  contractility  which  propels 
them. 

Q.  What  objections  are  there  to  the  doctrine  of  the 
heart's  agency  in  the  capillary  circulation? 

»#.  The  vessels  of  the  capillary  circulation  exhibit  a 
motion  different  from  that  of  the  heart  and  arteries;  where 
the  heart's  action  is  increased,  the  exhalations  are  not,  and  the 
secretions  are  actually  diminished;  in  some  haemorrhagies 
the  pulse  is  very  weak;  the  existence  of  local  external  dis- 
eases, and  the  inequality  of  growth  in  different  parts;  all 
these  invalidate  the  doctrine  alluded  to  in  the  question, 
and  substantiate  the  opinion  that  the  capillaries  act  inde- 
pendently. 

Q.  Founding  the  division  on  the  circulation  of  the 
blood,  and  that  of  the  capillaries,  how  do  you  divide  dis- 
eases? 


CAPILLARY    SYSTEMS,  149 

«tf.  Into  those  which  involve  the  general  circulation, 
and  those  which  belong  to  the  capillary. 

Q.  Give  examples  of  these. 

«/?.  Fever  is  a  disease  of  the  general  circulation,  while 
the  capillaries  are  the  seats  of  eruptions,  tumours,  and  in- 
flammation. 

Q.  To  what  classes  of  animals  are  fevers  confined  ? 

«#.  To  those  with  large  vessels,  in  which  the  blood 
moves  in  mass;  where  there  is  no  other  circulation  than 
capillary,  fever  cannot  exist. 

Q.  Which  is  the  most  essential  circulation? 

*#.  The  capillary,  for  there  is  no  organized  being  with- 
out it,  but  there  are  those  without  the  larger  or  general 
circulation. 

Q.  When  there  is  irregular  motion  of  the  blood  in  the 
capillaries  of  one  part,  how  is  the  relation  between  the 
veins  and  arteries  preserved? 

*#.  When  obstructed  in  one  part  of  the  capillary  sys- 
tem, the  determination  of  blood  to  another  portion  of  that 
system  is  increased. 

Q.   Is  the  whole  capillary  system  ever  affected  ? 

*#.  No — death  is  the  inevitable  result  of  such  a  state. 

Q.  What  is  a  most  important  law  of  the  vital  forces? 

<ft.  That  when  increased  in  one  part,  it  is  necessarily 
at  the  expense  of  other  parts. 

Q.  How  do  you  account  for  the  uneasy  sensations  ex- 
perienced under  atmospheric  changes? 

*ft.  They  are  the  effects  of  greater  or  less  atmospheric 
pressure  on  the  equilibrium  of  internal  and  external  capil- 
lary circulation. 

Q.  What  important  principle  as  to  blood-letting  results 


150  CAPILLARY    SYSTEMS. 

from  this  separate  view  of  the  general  and   capillary  cir- 
culation ? 

«#.  That  by  general  blood-letting  you  do  affect  the  ge- 
neral circulation,  but  at  the  same  time  you  do  not  neces- 
sarily remove  local  irritation  or  capillary  congestion. 

Of  the  Capillaries  considered  as  the  seat  of  the  produc- 
tion of  tftnimal  Heat. 

Q.  What  is  Bichat's  theory  of  animal  heat? 

Jl.  That  caloric  is  taken  in  the  processes  of  digestion, 
respiration,  and  perhaps  by  cutaneous  absorption;  in  the 
general  circulation  it  is  combined;  in  the  capillaries  it  is 
evolved,  giving  out  animal  heat.  Thus  it  is  with  nutri- 
tive matter;  it  is  taken  in,  combined  with  the  general,  and 
separated  in  the  capillary  system. 

Q.  What  then  is  the  process  of  animal  heat? 

t/?.   It  is  a  function  of  the  general  capillary  system. 

Q.  How  is  this  explanation  more  probable  and  rational 
than  the  chemical,  and  mechanical  theories  of  heat? 

Ji.  It  is  founded  on  a  uniformity  in  the  operations  of 
physiological  nature. 

Q.  Is  animal  heat  greater  in  animals  that  respire? 

«/?.  It  is;  and  the  size  of  the  lungs  seems  to  influence 
the  temperature. 

Q.  Does  pathology  confirm  this  theory  of  animal  heat? 

Ji.  It  does;  animal  heat  is  dependant  on  the  state  of  the 
vital  forces ;  and  when  these  forces  are  increased  in  inflam- 
mation and  in  disease,  the  heat  is  increased.  On  the  con- 
trary, in  those  cases  where  the  vital  forces  are  diminish- 
ed, the  heat  is  lessened. 


CAPILLARY    SYSTEMS.  151 

Q.   Have  the  tissues  different  temperatures? 

Jl.  They  have.  There  is  less  in  the  hair,  nails,  epi- 
dermis. There  is  less  heat  in  the  white  organs  than  in 
the  red. 

Q.  If  this  be  the  case,  how  is  the  general  temperature 
uniform? 

«/#.  The  tissues  which  evolve  much  caloric  supply  those 
which  do  not  eliminate  so  much. 

Q.  How  do  you  account  for  the  peculiar  sensations  of 
heat  in  the  different  tissues? 

e#.  Each  has  its  peculiar  heat,  as  it  has  of  secretion. 
All  these  varieties  result  from  the  modification  of  the 
vital  forces  of  the  part.  Animal  bodies  alone  exhibit  these 
varieties  of  heat. 

Q.  How  is  the  heat  increased  in  the  action  of  fever? 

Ji.  By  the  shock  given  to  the  capillary  system,  increas- 
ing its-  insensible  organic  contractility. 

Q.   Why  is  heat  increased  by  hurried  respiration?   - 

*ft.  Because  the  circulation  is  likewise  increased,  and 
consequently  the  vital  forces  of  the  capillaries.  The  ma- 
terial of  heat  is  more  freely  absorbed  in  hurried  than  slow 
respiration. 

Q.  Is  all  the  heat  of  red  blood  lost  in  its  change  to 
black  blood? 

•ft.  It  is  not;  hence  in  cases  of  sudden  death  from 
asphyxia  for  example,  heat  remains  some  time  after 
death. 

Q.  Why  does  heat  remain  longer  in  sudden  than  slow 
death? 

«/?.  Because  in  sudden  death  the  great  functions  are  in- 
terrupted, but  the  tonic  forces  remain  for  some  time. 


152  CAPILLARY    SYSTEMS, 

Q.  Mention  some'of  the  effects  of  sympathy  on  animal 
heat. 

«#.  In  syncope  it  is  greatly  reduced;  in  phthisis  the 
hands  and  feet  burn;  in  fever  the  heat  is  locally  or  gene- 
rally increased.  Now,  in  all  these  cases,  the  vital  forces 
of  the  parts  are  sympathetically  changed. 

Q.  How  do  you  account  for  the  sensations  of  heat  in 
a  part  which  are  so  delusive,  that  the  parts  to  a  bystander 
feel  cold? 

•fl.  This  is  a  sympathy  of  animal  sensibility;  whereas 
actual  increase  of  heat  is  a  sympathy  of  organic  sensi- 
bility. 

Q.  Why  in  the  natural  state  of  the  body  is  only  a  cer- 
tain temperature  developed  ? 

«/?.  It  is  not  known ;  nor  is  it  known  why  the  pulse  beats 
a  given  number  of  times  in  a  minute,  nor  why  a  certain 
number  of  respirations  are  made  in  the  same  time.  It 
may  be  said  that  this  is  the  primitive  order  of  the  vital 
actions. 

II.  PULMONARY  CAPILLARY  SYSTEM. 

Q.  What  do  you  mean  by  this  pulmonary  capillary 
system  ? 

A.  Exclusively  the  system  of  vessels  between  the  pul- 
monary artery  and  the  pulmonary  veins. 

Q.  In  regarding  this  system,  what  distinction  is  to  be 
drawn? 

«#.  That  it  be  not  confounded  with  the  capillaries  be- 
tween the  bronchial  arteries  and  veins;  they  are  attached 
to  the  general  capillary  system. 


CAPILLARY    SYSTEMS.  153 

Q.  Considering  the  difference  in  capacity  between  the 
general  capillary  circulation,  and  that  composing  the  pul- 
monary capillary  system,  how  do  all  the  blood  of  the 
first  and  the  chyle  and  the  lymph,  pass  through  the  second 
or  pulmonary  system? 

«/?.  Recollect  first  that  all  the  fluids  in  the  general  ca- 
pillary system  are  not  blood;  that  much  of  the  blood  in 
the  capillaries  is  expended  in  the  functions  of  the  parts 
through  which  it  passes,  as  in  secretion,  exhalation,  and 
nutrition;  that  the  course  of  the  blood  is  irregular  in  the 
general,  but  direct  in  the  pulmonary  capillary  system  from 
the  arteries  to  the  veins;  that  the  blood  in  the  pulmonary 
capillaries  has  no  function  to  subserve;  that  blood  flows 
much  more  rapidly  and  uninterruptedly  from  the  right 
ventricle  to  the  left  auricle,  because  the  course  is  shorter 
and  more  direct,  than  from  the  left  auricle  through  the 
body  to  the  right  ventricle ;  that  the  blood  gains  in  time 
of  passage  what  is  wanting  in  capillary  space. 

Q.  Why  are  the  lungs  so  frequently  inflamed? 

•#.  Because  of  direct  exposure  to  irritation  in  respira- 
tion, and  because  of  their  active  sympathies  with  other 
tissues,  especially  the  skin. 

Q.  Does  the  red  or  black  blood  become  congested  in 
the  lungs,  in  their  inflammation? 

Ji.  It  is  reasonable  to  believe  that,  from  the  sudden 
manner  in  which  extensive  congestions  appear  in  the  lungs, 
that  the  bronchial  arteries  could  not  supply  them;  it  is  there- 
fore the  black  blood  which  accumulates  in  congestion. 

Q.  How  can  this  crowding  of  the  lungs  with  sangui- 
neous congestion  be  ascertained? 

.#.  By  percussion. 

20 


154  CAPILLARY    SYSTEMS. 

Q.  What  predisposes  the  lungs  to  hepatization  ? 

Jl.  The  readiness  with  which  they s  receive  large  quan- 
tities of  fluid. 

Q.  Is  it  blood  which  fills  the  lungs  in  disease? 

«#.  It  is  not;  for  on  pressing  diseased  lungs,  the  fluid 
will  be  white,  or  even  purulent. 

Q.  Are  sacs  of  pus,  or  vomicse,  frequently  found  in  the 
lungs? 

t#.  They  are  rare;  the  pus  is  effused  into  the  substance 
of  the  lungs. 

Q.  Does  the  blood,  in  inflammation  of  the  lungs,  enter 
vessels  naturally  conveying  white  fluids? 

«#.  It  is  not  certain  that  there  are  such  vessels  in  the 
lungs ;  it  is  most  probable  that  the  blood  engorges  its  ac- 
customed channels,  or  it  is  exhaled  into  the  pulmonary 
texture,  overwhelming  its  functions. 

Q.  How  does  the  whole  blood  of  the  body  pass  through 
the  destroyed  lungs,  in  phthisis  pulmonalis? 

*ft.  The  quantity  of  blood  in  the  body  is  diminished  in 
proportion  as  the  pulmonary  lesion  progresses;  an  evi- 
dence of  this  diminution  of  the  quantity  of  blood  is  found 
in  the  feeble  pulse. 

Q.  What  would  be  the  consequence  of  transfusing  blood 
into  the  vessels  of  phthisical  persons? 

Jl.  The  lungs  could  not  bear  any  disproportion  of  blood, 
induced  in  that  way. 

Q.  Would  the  same  objection  apply  to  transfusion  in 
haemorrhage? 

.#.  It  would  not,  because  in  that  case  there  is  simply  a 
want  of  fluid  without  lesion  of  the  lungs;  the  increase  by 
transfusion  would  but  supply  the  materials  for  the  pulmo- 
nary function. 


CAPILLARY    SYSTEMS.  155 

Q.  How  does  blood-letting  act  in  inflamnYation  of  the 
lungs? 

*fl.  It  acts  by  decreasing  the  quantity  of  blood  which 
enters  the  organ;  it  diminishes  the  irritation  of  the  vital 
forces  which  draws  blood  to  the  part  and  retains  it.  You 
well  know  that  as  irritation  in  a  part  is  removed,  the  flow 
of  blood  diminishes. 

Q.  How  does  Beclard  say  the  erectile  tissue  is  formed  ? 

£.  He  says  it  is  composed  of  small  arteries  and  veins, 
which  intercommunicate  as  the  capillary  net- work  does; 
and  that  there  is  a  much  greater  developmentof  the  branches 
of  the  veins  in  the  erectile  tissue. 


(     156    ) 


EXHALENT  SYSTEM. 

Q.   In  what  respects  do  exhalation  and  secretion  agree? 

Jl.  In  this,  that  both  operations  separate  fluids  differ- 
ent from  the  blood. 

Q.   In  what  respects  do  exhalation  and  secretion  differ? 

*#.  Chiefly  in  these  particulars;  that  in  the  secreting 
organs  there  is  an  intermediate  organ  between  the  arteries 
and  excretories,  but  there  is  none  between  the  arterial 
terminations  and  the  exhalents;  that  the  secreted  fluids 
are  much  more  complicated  than  those  which  are  exhaled; 
that  exhalation  takes  place  from  an  infinite  number  of  dis- 
tinct vessels,  while  the  secreted  fluids  are  directed  to  one 
or  two  tubes  which  convey  them  from  the  organ;  that  the 
secreted  fluids  are  thrown  off,  becoming  excrementitious, 
while  the  exhaled  are  most  of  them  recrementitious ;  that 
numerous  surfaces  receive  the  exhaled  matters,  while  the 
secreted  are  principally  poured  out  on  the  mucous  and 
cutaneous. 

Q.  Name  some  of  the  exhaled  fluids. 

»/?.  There  is  the  fat,  and  the  serum,  the  synovia,  the 
marrow. 

Q.   Now  indicate  some  of  the  secretions. 

*#.  You  have  the  bile,  urine,  semen,  pancreatic  fluid, 
saliva,  and  others. 

Q.  What  do  you  mean  by  exhalents? 

*ft.  They  are  small  tubes  or  vessels  arising  from  the 
capillary  system,  continuous  with  the  arteries  which  bring 
them  the  materials  for  exhalation. 


EXHALENT    SYSTEM.  157 


General  Arrangement  of  the  Exhalents. 

Q.   How  are  the  exhalents  divided? 

*fl.  Into  three  orders;  those  terminating  on  the  outlets 
at  the  cutaneous  and  mucous  surfaces,  those  which  termi- 
nate on  the  internal  organs,  and  those  which  convey  the 
nutritive  matter. 

Properties  and  Functions  of  the  Exhalent  System. 

Q.  What  are  the  properties  of  the  exhalents? 

Jl.  Destitute  of  animal  sensibility  and  animal  contrac- 
tility, their  vital  properties  on  which  their  functions  de- 
pend are  organic  sensibility  and  insensible  organic  con- 
tractility. 

Q.  How  is  it  that  the  exhalents  of  the  different  organs 
and  surfaces  pour  out  uniformly  their  appropriate  fluids? 

«#.  As  the  blood  whence  the  exhaled  fluids  are  derived, 
is  in  all  organs  the  same,  the  power  by  which  each  organ 
separates  its  own  fluid  must  result  from  peculiarity  in  the 
organic  sensibility  and  contractility  of  these  organs. 

Q.  Will  you  be  more  explicit  on  this  subject? 

t/#.  It  is  either  because  the  blood  whence  the  exhalation 
proceeds  is  specifically  distinct  in  the  various  surfaces,  or 
the  vital  properties  of  the  solids  so  differ  as  to  produce  the 
various  exhalations.  There  is  nothing  concerned  in  the 
process  but  the  blood  and  the  solids  which  it  stimulates. 

Q.  To  what  has  exhalation  been  ascribed  ? 

«#.  To  a  distillation  through  the  coats  of  the  arteries. 

Q.  How  do  you  account  for  morbid  or  altered  exhala- 
tions? 


158 


EXHALENT    SYSTEM. 


«/?.  They  depend  on  deranged  organic  sensibility,  a 
change  of  relation  between  it  and  the  blood. 

Q.  How  is  this  organic  sensibility  deranged  in  the  ex- 
halents? 

«#.  By  the  direct  impression  of  irritation,  by  sympa- 
thetic power,  and  in  an  unknown  way. 

Q.  Give  an  instance  of  direct  irritation  of  the  exha- 
lents. 

\ft.  You  see  it  in  the  action  of  cold  on  the  skin. 

Q.  Give  an  example  of  sympathetic  impression  on  the 
exhalents. 

t/2.  An  instance  is  found  in,  the  sweating  which  is  in- 
duced by  pain  in  the  fibrous  and  muscular  tissues. 

Q.  What  exhalents  are  exclusively  exposed  to  direct 
stimulation? 

«#.  The  exhalents  of  the  skin  and  mucous  membranes; 
besides  this  exposure  to  direct  irritation,  they  are  liable 
to  the  sympathetic  derangements;  and  hence  they  are  more 
frequently  diseased  than  any  other  exhalents. 

Q.  Are  all  the  exhalations  simultaneously  diminished 
or  increased? 

«#.  In  fever  they  are  all  diminished.  As  a  general  rule, 
when  one  exhalation  is  increased  another  is  diminished; 
as  you  see  the  hectic  sweats  in  phthisis  diminished  by  the 
dropsical  infiltrations  which  come  on  in  the  last  stages  of 
the  disease. 

Q.   How  are  morbid  exhalations  divided? 

«#.  Into  those  attended  with  exalted  vital  forces,  and 
those  where  these  forces  are  diminished. 

Q.  What  are  preternatural  exhalations? 

*fl.  Any  discharges  from  the  exhalents  which  differ 
from  the  natural. 


EXHALENT    SYSTEM.  159 

Q.  What  exhalents  most  frequently  pour  out  blood? 

t/?.   The  mucous. 

Q.  What  are  the  evidences  that  these  mucous  haemor- 
rhages are  exhalations? 

«/?.  The  mucous  surfaces,  though  minutely  examined 
after  death,  show  no  ruptured  points;  pressure  on  the 
uterus  after  death  during  menstruation  exhibits  an  issue 
of  bloody  drops,  but  no  rupture  can  be  seen;  the  womb 
would  exhibit  a  surface  of  cicatrices,  if  haemorrhages  pro- 
ceeded from  erosion;  the  sudden  translation  of  haemor- 
rhages from  one  part  to  another,  under  sympathetic  laws, 
tend  to  confirm  the  doctrine  of  exhalation  rather  than  rup- 
ture; the  causes  of  haemorrhage  from  rupture  are  so  dif- 
ferent from  those  of  spontaneous  haemorrhage;  and  lastly, 
these  accidental  haemorrhages  are  not  under  the  laws  of 
sympathy,  as  the  spontaneous  are. 

Q.  What  is  the  anatomical  distinction  between  haemor- 
rhage and  inflammation? 

t/?.  In  inflammation  the  blood  accumulates  in  the  capil- 
laries; in  haemorrhage  the  blood  passes  out  from  (he  arte- 
ries l>y  the  exhalents. 

Q.  Is  it  not  probable  that  the  irritation  is  differently 
located  in  the  two  diseases? 

Ji.  Perhaps  it  is  seated  in  different  vessels  in  haemor- 
rhage and  inflammation. 

Q.  What  proof  have  you  that  in  active  haemorrhage  the 
organic  sensibility  is  altered? 

*fl.  The  previous  symptoms  of  heat,  pain,  itching,  show 
that  it  is  altered. 

Q.  In  passive  haemorrhages  how  are  the  vital  forces  of 
the  exhalents  affected? 


160  EXHALENT    SYSTEM. 

.#.  The  organic  sensibility  and  insensible  organic  con- 
tractility are  diminished. 

Q.  What  locality  has  haemorrhage  in  organic  disease? 

A.  Proximity  to  the  mucous  surface  governs  it;  for  in- 
stance, when  the  liver  is  diseased,  the  haemorrhage  will  be 
from  the  mucous  expansion  of  the  stomach  or  intestines; 
when  the  heart  is  diseased,  the  bleeding  will  be  from  the 
pulmonary  mucous  tissue. 

Q.  Does  the  whole  mucous  tissue  ever  pour  out  blood 
at  one  time? 

•ft.  Never. 

Q.  Why  are  the  mucous  tissues  so  liable  to  haemor- 
rhage ? 

«/?.  The  short  course  of  the  blood  in  the  capillaries  to 
the  mucous  surfaces,  and  the  general  fulness  of  these  tis- 
sues with  blood. 

Q.  Which  mucous  surfaces  are  least  liable  to  haemor- 
rhage ? 

«/?.  Those  lining  the  sinuses  of  the  face  and  ear. 

Q.   Is  plethora  necessary  to  active  haemorrhage? 

«#.  It  is  not;  for  a  mere  local  increase  or  alteration  oi 
the  vital  forces  will  produce  it.  Hence  there  may  be  ac- 
tive haemorrhage  without  plethora. 

Q.  How  will  you  account  for  the  varieties  in  the  quan- 
tity of  the  menstrual  discharge  ? 

A.  It  varies  as  the  vital  forces  of  each  uterus  do. 

Q.  What  essential  difference  must  be  observed  in  the 
treatment  of  capillary  and  exhalent  haemorrhage,  and  ar- 
terial ? 

Jt.  In  the  haemorrhage  from  the  two  first  named  sources, 
medicines  which  act  on  the  organic  sensibility  of  the  part 


EXHALENT    SYSTEM.  161 

are  successful ;  but  in  the  case  of  the  bleeding  artery  they 
have  no  effect. 

Q.  How  do  you  know  that  blood  found  in  serous  cavi- 
ties is  exhaled? 

•ft.  Because,  after  the  most  critical  examination,  no  ero- 
sion could  be  ascertained. 

Q.  What  serous  cavities  are  least  liable  to  these  bloody 
exhalations? 

•ft.  The  tunica  vaginalis  testis,  and  the  tunica  arach- 
noides. 

Q.  Are  the,  bloody  exhalations  in  serous  cavities  always 
from  active  haemorrhage  ? 

•ft.  The  exhalation  of  blood  in  these  cavities  is  some- 
times passive. 

Q.  Does  the  water  in  anasarca  being  reddish,  imply 
active  haemorrhage  or  febrile  dropsy  ? 

A.  It  does  not,  for  the  fluid  of  dropsy  is  often  of  this 
reddish  hue  in  passive  cases. 

Q.  Are  preternatural  exhalations  uniform? 

•ft.  They  vary  very  much,  as  you  may  see  in  the  vari- 
ous aspects  of  fluids  in  the  different  serous  cavities. 

Q.  Why  are  not  secretions  exhaled  as  well  as  fat,  se- 
rum, and  other  fluids? 

•ft.  Because  the  glandular  apparatus  is  different  from  the 
exhalent. 

Q.  How  does  Mascagni  suppose  exhalations  to  be 
made? 

<ft.  By  lateral  pores  in  the  vessels. 


(      162 


ABSORBENT  SYSTEM. 

Q.  What  do  you  mean  by  the  absorbent  system? 

«/?.  It  is  a  series  of  vessels,  .uniting  in  trunks,  and  en- 
larging occasionally,  so  as  to  form  what  are  improperly 
termed  glands. 

Of  the  Msorbent  Vessels. 

Q.  Where  do  the  absorbents  arise  ? 

«/?.   They  take  their  origin  from  every  part  of  the  body. 

Q.  Where  do  the  trunks  of  this  system  of  vessels  ter- 
minate? 

•#.   In  the  vena  cava  of  the  black  blood  system. 

Q.  Why  are  the  enlargements  of  these  vessels  impro- 
perly called  glands? 

*/2.  Because  they  do  not  pour  out  fluids  by  excretories 
arising  from  them. 

Q.   What  is  the  general  division  of  the  absorbents? 

•#.  Into  the  exterior  and  interior  absorbents. 

Q.  What  is  the  difference  between  the  exterior  and  in- 
terior absorbents? 

rf.  The  external  absorbents  do  not  take  up  the  fluids 
exhaled;  those  on  the  skin  do  not  absorb  the  perspiration ; 
nor  do  the  mucous  absorbents  take  up  the  pulmonary  or 
gastric  exhalations.  They  absorb  foreign  matters.  The 
internal  absorbents  are  constantly  engaged  in  taking  up 
what  is  exhaled. 


ABSORBENT    SYSTEM.  163 

Q.  What  is  it  that  renders  absorption  of  the  solids 
practicable  for  such  delicate  vessels  as  the  absorbents? 

.tf.  Solids,  like  fluids,  are  composed  of  minute  par- 
ticles, and  vessels  remove  a  particle  of  the  one  as  they  do 
of  the  pther. 

Q.  In  what  system  do  the  absorbents  arise? 

tfi.   Of  course  they  arise  in  the  capillary  tissue. 

Q.  How  are  the  absorbents  of  the  extremities  divided  ? 

'•&.  Into  the  superficial  and  the  deep-seated. 

Q.   How  are  the  absorbents  of  the  trunk  divided? 

t#.  Into  the  superficial  and  deep-seated  of  the  parietes 
of  the  trunk  of  the  body;  and  into  the  superficial  and  deep- 
seated  of  the  viscera. 

Q.   Where  have  they  not  yet  been  found  ? 

»#.  In  the  cavity  of  the  cranium. 

Q.  In  form  how  do  the  absorbents  differ  from  the 
veins? 

«#.  The  absorbents  do  not  enlarge  in  their  course  as 
the  veins  do;  they  compensate  for  their  small  size  by  the 
number  of  tubes. 

Q.  How  can  you  have  the  best  natural  view  of  the  ab- 
sorbents? 

«#.  By  examining  the  concave  surface  of  the  liver,  very 
speedily  after  opening  the  abdomen  of  the  dog  or  other 
large  animal. 

Q.   In  what  disease  are  they  often  remarkably  enlarged  ? 

«/?.   In  dropsy. 

Q.  What  constitutes  the  difficulty  in  deciding  on  the 
capacity  of  the  absorbents? 

Ji.  The  same  as  in  the  case  of  the  veins;  both  veins  and 
absorbents  are  so  extensible  and  contractile,  as  to  be  ever 
varying  in  size. 


164 


ABSORBENT    SYSTEM. 


Q.  Do  they  resemble  the  veins  in  any  other  respects? 

*#.  They  resemble  them  in  their  frequent  anastomoses; 
in  the  aids  the  motion  of  their  fluids  require  and  receive 
from  adjacent  pressure,  and  in  the  influence  of  gravity  on 
their  fluids. 

Q.  Why  are  the  legs  more  swelled,  in  dropsy,  in  the 
evening  than  in  the  morning? 

*#.  Because  of  the  influence  of  gravity  on  the  absorb- 
ents debilitated  by  disease. 

Q.  Why  does  the  arm  swell  more  from  pressure  of  the 
head  of  the  humerus  in  the  axilla  in  certain  cases,  than 
when  extensive  pressure  is  made  on  the  upper  part  of  the 
arm? 

*#.  Because  in  the  axilla  a  greater  number  of  absorbents 
are  compressed,  and  swelling  of  the  limb  below  them 
rather  depends  on  this  circumstance  than  on  the  extent  of 
the  surface  compressed. 

Q.  What  visceral  enlargement  has  the  greatest  influence 
in  tumefying  the  lower  extremities? 

»#.  That  of  the  uterus,  because  in  its  enlargement  it  com- 
presses the  greatest  number  of  absorbents. 

Q.  Have  the  other  abdominal  viscera  the  power  of  pro- 
ducing infiltration  by  this  pressure  ? 

«#.  They  have  not;  and  when  this  infiltration  arises  in 
the  diseases  of  other  viscera,  it  is  not  from  pressure  but 
from  an  increase  in  the  vital  forces  of  the  exhalents. 

Q.  What  has  heretofore  been  the  ascribed  cause  of 
dropsy  from  these  visceral  enlargements? 

*#.  It  was  ascribed  to  an  obstruction  of  the  venous 
blood  causing  effusion ;  but  it  is  really  owing  to  an  ob- 
struction to  the  absorbents. 

Q.  What  is  the  structure  of  the  absorbents? 


ABSORBENT    SYSTEAf.  165 

•ft.  A  dense  cellular  coat,  and  a  lining  membrane  con- 
tinuous with  that  of  the  veins.  There  is  no  fleshy  fibre  ob- 
servable in  the  absorbents. 

Q.  What  are  the  peculiarities  of  this  internal  lining 
membrane  of  the  absorbents? 

•ft.  It  is  in  the  dead  body  bedewed  by  an  unctuous,  and 
in  the  absorbents  of  the  external  surface  of  the  lungs  fre- 
quently covered  with  a  white  matter  which  resembles 
plaster. 

Of  the  Lymphatic  Glands. 

Q.  What  peculiarities  attend  the  situations  of  the  lym- 
phatic glands? 

Jl.  They  are  most  abundant  where  cellular  texture 
abounds,  and  they  are  more  numerous  as  they  approach 
the  common  trunks. 

Q.  What  is  the  colour  of  the  glands? 

•ft.  They  are  red  in  childhood,  gray  in  adult  life,  and 
yellowish  in  old  age. 

Q.  At  what  period  of  life  are  they  most  developed? 

•ft.  They  are  more  fully  developed  in  childhood;  they 
are  least  so  in  old  age. 

Q.  These  glands  have  a  common  and  a  peculiar  texture 
— what  are  they? 

•ft.  The  common  texture  is  a  loose  and  dense  cellular 
investment;  the  peculiar  texture  is  a  pulpy  matter,  of 
greater  or  less  density,  resembling  the  pulp  of  the  nervous 
ganglions. 


166  ABSORBENT    SYSTEM. 

Properties  of  the  Absorbent  System. 

Q.  What  properties  of  texture  do  the  absorbents  and 
glands  possess? 

*fl.   Extensibility  and  contractility. 

Q.  What  vital  properties  attach  to  them? 

*#.  But  little  animal  sensibility  in  health,  but  consider- 
able in  diseases.  They  have  no  animal  contractility.  Ob- 
viously, they  have  organic  sensibility  and  insensible  or- 
ganic contractility. 

Q.  What  remarkable  phenomenon  attends  these  two 
last  named  properties  in  the  absorbents? 

«/?.  The  organic  sensibility  and  the  insensible  organic 
contractility  continue  some  hours  after  death  in  some  bo- 
dies; or  in  other  words,  absorption  continues  after  death. 

Q.  How  does  the  organic  sensibility  of  the  absorbents 
differ  from  that  of  the  glands? 

«#.  In  the  absorbents  it  is  in  relation  to  many  fluids; 
glands  admit  but  one. 

Q.  What  difference  appears  between  the  lining  mem- 
brane of  the  absorbents  and  that  of  the  veins? 

«#.  The  greater  susceptibility  of  the  first  to  inflamma- 
tion. 

Q.  What  is  a  common  consequence  of  inflammation  of 
the  lymphatic  glands? 

t/2.  Scirrhus  hardness  much  more  frequently  follows 
inflammation  in  them  than  in  other  structures. 

Q.  What  shows  a  difference  between  the  vital  proper- 
ties of  the  absorbents  and  lymphatic  glands? 

Jl.  The  fact  that  the  glands  are  so  frequently  inflamed 
by  matters  which  do  not  affect  the  absorbents. 


ABSORBENT    SYSTEM.  167 


Q.  What  are  the  usual  causes  of  inflamed  lymphatic 
glands? 

Jl.  The  absorption  of  matter,  and  sympathetic  impres- 
sion. 

Q.  Give  instances  of  sympathetic  affection  of  the  glands. 

A.  You  see  them  in  axillary  or  inguinal  swelling  pro- 
ceeding from  the  prick  of  a  thorn,  a  blister,  or  any  other 
irritant  of  that  kind. 

Q.  In  what  way  are  the  lymphatic  glands  most  fre- 
quently inflamed  ? 

*#.  They  take  on  inflammation  in  the  progress  of  orga- 
nic visceral  disease;  the  glands  partaking  of  the  acute, 
chronic,  or  specific  action,  which  prevails  in  the  viscus.  In 
mammary  cancer  the  axillary  glands  are  diseased;  in 
scirrhus  stomach,  or  diseased  liver,  the  mesenteric  glands 
are  affected,  and  so  forth. 

Q.  How  does  an  enlarged  strumous  lymphatic  gland 
differ  from  one  enlarged  by  ordinary  causes? 

Jl.  In  the  strumous  enlargement  the  structure  of  the 
gland  is  at  first  affected;  in  those  enlarged  by  ordinary 
causes,  it  is  secondarily  involved.  The  scrofulous  glands 
have  a  whitish  substance,  which  finally  destroys  the  whole 
gland. 

Of  Absorption. 

Q.  Why  do  you  suppose  the  action  of  the  absorbents 
to  depend  on  vital,  and  not  on  capillary  power? 

Jl.  Because  fluids  are  received  or  rejected  according  to 
their  relation  to  the  organic  sensibility  of  the  absorbents; 
they  have  a  peculiar  organic  sensibility. 


16$  ABSORBENT    SYSTEM. 

Q.   How  do  medicines  act  in  producing  absorption? 
J%.  By  increasing  the  organic  sensibility  of  the  absor- 
bents; and  such  are  the  variations  in  the  degrees  to  which 
organic  sensibility  can  be  raised,  as  to  account  for  the  ab- 
sorption of  the  various  fluids. 

Q.  Will  these  considerations  account  for  the  introduc- 
tion of  morbific  matter  by  the  lungs  and  lacteals? 

•ft.  They  will;  for  if  the  organic  sensibility  of  the  lac- 
teals,  or  of  the  pulmonary  absorbents  be  increased,  they 
will  take  in  matters  which  in  their  healthy  state  would  be 
rejected. 

Q.  What  circumstances  vary  the  natural  type  of  the 
sensibility  of  the  absorbents? 

•#.  Direct  causes,  such  as  frictions  to  the  skin ;  and 
sympathetic  causes,  as  when  the  absorbents  are  acted  on 
by  a  distant  viscus. 

Q.  What  conspicuous  difference  appears  in  the  chan- 
nels of  the  veins  and  absorbents? 

*ft.  The  fluid  in  the  absorbents  has  to  pass  through  nu- 
merous glands,  in  each  of  which  is  a  kind  of  capillary 
system;  this,  while  it  affects  the  course  of  the  lymph,  may 
also  when  the  glands  are  diseased,  change  the  quality  of 
the  lymph.  The  veins  have  no  such  glands  to  pass  through 
in  their  progress  to  the  heart. 

Q.  What  three  phenomena  always  accompany  each 
other  in  the  organs? 

J2.  Great  development,  attended  by  activity  of  func- 
tion, these  giving  rise  to  disposition  to  disease. 

Q.  What  reference  has  the  answer  to  the  last  question 
to  the  absorbent  glands? 

»#.  In  childhood  there  is  great  development  of  the  ab- 


ABSORBENT    SYSTEM.  169 

sorbent  system;  at  that  period  of  life,  the  functions  of  this 
system,  whatever  they  may  be,  are  in  great  activity,  and 
there  is  great  disposition  to  disease  at  the  same  time. 

Q.  What  period  of  life  limits  the  predominance  of  the 
lymphatic  glands  ? 

A.  Puberty. 

Q.  At  what  ages  do  external  absorption  and  nutritive 
absorption  predominate  ? 

«/?.  In  childhood  and  youth  the  external  absorbents  are 
most  active;  in  advanced  life  the  nutritive  absorption  is 
greatest. 

Q.  Explain  this  expression,  nutritive  absorption. 

A.  By  it  is  meant  that  preponderance  of  absorption  in 
advanced  life  over  nutrition,  which  leads  to  the  emaciation 
of  age. 

Q.  Why  do  encysted  tumours  increase  so  regularly, 
and  in  some  cases  so  rapidly? 

t/2.  Because  absorption  in  them  is  feeble  compared  to 
exhalation. 

Q.  What,  according  to  Beclard,  is  the  actual  structure 
of  a  gland  ? 

*#.  There  are  vessels  going  to  and  from  the  gland;  they 
communicate  as  the  veins  and  arteries  do;  and  there  are 
little  cavities  or  sacs  somewhat  resembling  the  cells  of 
the  erectile  textures. 

Q.  Is  it  certain  that,  as  Bichat  thinks,  the  absorbents 
do  not  possess  sensible  organic  contractility  ? 

«/?.  German  physiologists  have  ascertained  that  certain 
irritants  occasion  a  contraction  of  the  thoracic  duct;  and 
as  this  does  not  result  from  the  horny  hardening,  it  is  le- 
gitimately ascribed  to  sensible  organic  contractility. 

22 


170  ABSORBENT    SYSTEM. 


PATHOLOGY  or  THE  ABSORBENT  SYSTEM. 

Q.  What  are  the  diseases  of  this  system  ? 

«#.  Inflammation,  induration,  scrofula,  ossifications,  can- 
cer, lymphatic  varix,  sympathetic  bubo. 

Q.  How  should  this  tissue  be  divided  in  considering  its 
diseases? 

«/?.  There  are  the  diseases  of  the  lymphatic  glands,  as 
they  are  improperly  termed,  and  those  of  the  vessels. 

Q.  At  what  period  of  life  are  these  diseases  most  fre- 
quent? 

«/2.   In  childhood;  they  are  infrequent  in  age. 

Q.  What  are  the  divisions  of  diseases  of  this  tissue? 

A.  They  are  idiopathic  and  symptomatic  diseases. 

Q.   Divide  the  inflammations  of  the  lymphatic  glands. 

.#.   They  are  acute  and  chronic,  simple  or  specific. 

Q.  How  is  this  inflammation  excited? 

*#.  By  a  remote  irritant,  or  by  absorbing  a  poison 
which  comes  into  contact  with  a  gland. 

Q.  Is  the  absorbent  which  conveys  a  poison  to  a  gland 
necessarily  inflamed  thereby? 

*/?.  It  is  not;  the  gland  may  be  inflamed  alone,  or  both 
vessel  and  gland  may  be. 

Q.  What  glands  are  most  liable  to  inflammation  ? 

*/?.  Those  of  the  axilla  and  groin. 

Q.  What  peculiarity  is  there  in  the  symptoms  of  in- 
flamed glands? 

Jl.  The  pain  is  less  acute,  and  the  progress  slower  than 
in  phlegmon. 

Q.  Where  is  the  matter  formed  in  a  lymphatic  gland  ? 


ABSOHBENT    SYSTEM.  171 

•fL  la  the  centre  of  it.  The  gland  is  not  disorganized, 
but  enlarged  and  inflamed. 

Q.   What  absorbent  vessels  are  principally  inflamed  ? 

J3.   Those  of  the  inferior  extremities. 

Q.  Where  is  the  scrofulous  affection  of  this  tissue  most 
common? 

•ft.  In  the  abdomen,  thorax,  and  neck. 

Q.   What  occasions  marasmus  in  tabes  mesenterica? 

•ft.  The  gradual  diminution  in  the  absorption  of  the 
chyle,  owing  to  progressive  destruction  of  the  function 
and  organization  of  the  mesenteric  glands. 

Q.  How  is  the  dyspnoea  from  tabes  mesenterica  pro- 
duced? 

*ft.  By  co-existent  though  consecutive  disease  in  the 
lymphatics  of  the  lungs. 

Q.  What  are  the  progressive  stages  in  the  scrofulous 
disease  of  a  lymphatic  gland? 

•ft.  The  gland  is  first  in  chronic  inflammation;  next  it 
is  in  part  steatomatous,  then  it  is  completely  steatomatous, 
and  lastly  it  degenerates  into  the  formation  of  bad  pus  and 
ichorous  fluid.  In  adopting  this  view,  ascertain  whether 
the  scrofulous  degeneration  is  altogether  steatomatous. 

Q.  Why  are  not  scrofulous  swellings  of  the  neck  fatal? 
-  •ft.  Because  their  progress  is  bounded  by  parts  not  dis- 
posed to  take  on  disease,  or  not  vital  if  they  do. 


(     172     ) 


OF  SYSTEMS  PECULIAR  TO  CERTAIN 
APPARATUS. 

Q.   What  systems  have  heretofore  been  considered? 

*#.  Such  as  may  be  termed  primitive;  such  as  are  com- 
mon to  all  parts;  those  which  form  the  nutritive  paren- 
chyma. 

Q.  What  tissues  remain  to  be  considered? 

ttf.  Those  which  belong  to  special  purposes  in  the  ani- 
mal economy. 

Q.  Explain  this  more  particularly  ? 

«#.  While  the  above  systems  are  general,  there  are  cer- 
tain others  which  are  not  so,  but  are  appropriated  to  cer- 
tain functions  separately  or  conjointly.  You  observe  that 
the  bones,  muscles  of  animal  life,  the  cartilages  and  fibrous 
tissue  appertain  to  locomotion;  while  the  serous,  mucous, 
and  organic  muscular  systems  are  particularly  directed  to 
digestion,  respiration,  and  circulation.  So  it  is  likewise 
with  the  glandular  tissue  which  belongs  to  secretion;  other 
examples  might  be  adduced. 

Q.  What  further  difference  is  observed? 

t/2.  The  primitive  are  universally  found  and  are  conti- 
nuous, as  the  cellular  tissue ;  the  special  tissues  are  insu 
lated,  and  separated  from  each  other  by  the  intervention 
of  organs,  as  the  bones. 


(    173    ) 


OSSEOUS  SYSTEM. 

Q.   What  is  this  system? 

t#.  A  tissue  characterized  by  hardness  and  resistance, 
admirably  calculated  for  a  base,  support  and  protection  of 
the  soft  parts. 

Forms  of  the  Osseous  System. 

Q.  What  are  the  forms  of  the  bones? 

.#.  They  are  long,  flat  and  short. 

Q.  To  what  purpose  in  the  animal  economy  are  the 
long  bones  principally  appropriated? 

«/?.   To  that  of  locomotion. 

Q.  Where  are  the  longest  bones  found? 

«#.  In  the  superior  parts  of  the  upper  and  lower  extre- 
mities. The  bones  diminish  in  their  length,  but  become 
more  numerous  as  you  approach  the  fingers  and  toes? 

Q.  What  is  the  consequence  of  this  location  of  the  long 
and  short  bones? 

.#.  That  the  superior  part  of  the  extremities  has  the 
most  extensive  motion,  while  the  inferior  part  has  the 
greatest  number  and  variety  of  limited  motions. 

Q.  What  is  the  general  conformation  of  these  long 
bones? 

«/?.  They  are  larger  at  the  extremities  tlwin  in  the  shaft, 
which  last  is  usually  rounded. 

Q.  What  advantages  result  from  these  enlarged  extremi- 
ties of  the  long  bones? 


174  OSSEOUS    SYSTEM. 

«#.  They  prevent  dislocations,  and  preserve  the  sym- 
metry of  the  limb  to  which  they  are  attached. 

Q.  What  general  features  are  conspicuous  in  the  bodies 
of  the  long  bdnes? 

t#.  The  ridges  for  the  implanting  of  aponeuroses;  and 
the  twist  in  most  of  these  bones. 

Q.   At  what  period  is  the  medullary  canal  formed  ? 

•ft.  At  the  period  of  ossification;  it  does  not  exist  at  the 
earliest  foetal  periods.  It  is  not  found  while  the  bone  is 
cartilaginous. 

Q.   How  is  this  canal  formed? 

Jl.  By  the  absorption  of  the  gelatine  in  the  centre,  no 
more  of  which  is  exhaled.  Observe  the  different  processes 
which  take  place  at  the  same  time  in  the  exterior  and  in- 
terior of  the  bone;  for,  while  the  absorbents  remove  the 
gelatine  and  thus  form  the  medullary  canal,  and  the  exha- 
lents  cease  to  deposite  gelatine,  the  exhalents  on  the  ex- 
ternal surface  of  the  bone  are  placing  a  wall  of  phosphate 
of  lime  to  give  the  bone  firmness  and  smoothness. 

Q.  In  what  bones  is  the  medullary  canal  found? 

*ft.  In  the  humerus,  in  the  radius,  in  the  ulna,  in  the 
femur,  in  the  tibia,  in  the  fibula,  and  in  the  clavicle. 

Q.  What  is  the  form  of  the  canal  ? 

•/#.   It  is  cylindrical  and  straight. 

Q.  What  are  the  uses  of  the  medullary  canal? 

t#.  It  gives  lodgement  and  protection  to  the  medullary 
organ,  and  renders  the  bone  stronger;  for  a  hollow  cylin- 
der will  be  less  apt  to  break  or  bend  than  a  full  one. 

Q.  What  would  be  the  inconveniences  of  a  solid  cylin- 
der for  the  shaft  of  a  bone?  "* 

•#.  They   would  impede  the  motion  of  the  limbs,  it 


OSSEOUS    SYSTEM.  175 

solid,  and  of  the  dimensions  of  the  hollow  cylinder;  and 
if  smaller  and  solid,  there  would  not  be  surface  enough 
for  the  insertion  of  muscles  and  aponeuroses. 

Q.   How  is  this  medullary  canal  affected  in  fractures? 

«#.  When  callus  is  first  formed,  gelatine  is  so  deposited 
as  to  close  the  canal;  but  this  gelatine  is  subsequently  ab- 
sorbed, and  the  continuity  of  the  canal  reinstated. 

Q.  What  purposes  do  the  flat  bones  serve  in  the  sys- 
tem? 

*#.  They  are  especially  appropriated  to  form  cavities. 

Q.  Are  the  cavities  usually  formed  of  one  or  many 
bones? 

*ft.  Of  many  bones;  and  hence,  in  part,  their  solidity, 
and  the  limits  set  to  their  fractures. 

Q.  Why  are  fractures  of  all  the  bones  more  infrequent 
in  children  than  in  adults? 

«#.  Because  ossification  being  incomplete,  the  bones 
yield  rather  than  break. 

Q.  What  is  the  form  of  the  flat  bones? 

t#.   They  have  a  convex  and  concave  surface.     The 
curve  forms  in  age  a  bony  arch;  a  mechanism  powerful 
for  strength  and  protection. 
.  Q.   At  what  part  is  a  flat  bone  thinnest? 

.#.  It  is  thinnest  in  the  centre;  the  circumference  being 
thickest,  forms  a  broader  surface  for  union,  and  offers 
points  for  muscular  origin  in  some  bones,  as  the  spine  of 
the  ilium. 

Q.   Are  there  cells  in  the  flat  bones? 

«#.   There  are;  they  are  between  the  two  layers. 

Q.  What  purposes  in  the  oeconomy  are  attained  by  short 
bones? 

•//.  The  two  great  ones  of  solidity  and  mobility;  hence 


176  OSSEOUS    SYSTEM. 

these  bones  are  found  in  the  spinal  column,  and  in  the 
hands  and  feet. 

Q.  How  does  their  number  give  solidity  or  strength  ? 

«#.  The  bands  requisite  to  unite  them  are  so  frequent 
and  strong  as  to  produce  these  effects. 

Q.  And  how  does  their  number  give  mobility? 

*ft.  Their  individual  motions  tend  to  communicate  ge- 
neral mobility. 

Q.  What  is  their  general  appearance  ? 

*ft.  They  are  very  rough,  with  cavities  and  eminences 
for  their  articulations,  for  their  muscles  and  ligaments. 

Q.  What  is  their  internal  structure? 

*ft.  They  are  almost  entirely  cellular. 

Q.  What  influence  has  this  structure  on  the  diseases  of 
these  short  bones? 

«#.  It  renders  them  liable  to  frequent  caries. 

Q.  What  is  the  general  name  of  the  bony  eminences? 

•ft.  They  are  usually  denominated  apophyses. 

Q.  What  do  you  mean  by  epiphyses? 

<ft.  They  are  points  of  bony  eminence,  which  are  not 
entirely  united  to  the  principal  bone  by  calcareous  union; 
epiphyses  are  united  to  the  bone  by  cartilage. 

Q.   How  are  the  bony  eminences  divided? 

«#.  Into  four  classes;  those  of  articulation,  of  insertion, 
of  reflection,  and  of  impression. 

Q.  What  are  attached  to  the  eminences  of  insertion  ? 

«#.  The  fibrous  organs  exclusively,  such  as  ligaments, 
tendons,  &c. 

Q.  Where  do  you  find  these  eminences  of  insertion 
most  conspicuous? 

«#.  In  strong  men,  in  carniverous  animals.  The  size 
of  these  protuberances  indicates  the  strength  of  the  animal. 


OSSEOUS    SYSTEM,  177 

Q.  What  do  you  mean  by  an  eminence  of  reflection? 

•ft.   One  under  which  a  tendon  passes  when  it  deviates  > 
from  its  original  course. 

Q.  What  are  the  external  cavities  of  bones  and  their 
uses. 

•ft.  They  give  increased  space  for  aponeurotic  and  liga- 
mentous  insertions;  they  receive,  lodge,  and  protect  organs 
or  portions  of  organs;  they  form  grooves  for  the  passage 
of  tendons;  they  transmit  nerves  and  blood-vessels  through 
the  bones,  and  those  vessels  which  nourish  the  bones. 

Q.  Are  these  grooves  for  the  tendons,  for  example,  those 
at  the  ends  of  the  long  bones,  formed  by  the  friction  and 
pressure  of  the  tendons,  or  are  they  of  natural,  primitive 
osseous  development? 

•ft.  If  formed  by  the  friction  of  tendons,  they  ought  to 
be  deep  or  superficial  in  proportion  to  the  action  of  the 
muscles  and  the  age  of  the  subject;  they  should  not  be 
found  in  the  foetal  cartilages;  they  would  be  very  slight 
in  infancy;  on  the  contrary,  they  are  fully  developed  at 
all  periods  of  life,  and  are  therefore  original. 

Q.  How  are  the  cavities  or  foramina  of  nutrition  in  the 
bones  divided? 

•ft.  There  is  that  in  the  body  of  the  bone  which  con- 
veys nutrition  to  the  medullary  canal;  there  are  those 
which  nourish  the  cellular  structure  at  the  ends  of  the 
bones;  and  there  is  a  third  set,  viz.  those  which  supply  the 
compact  texture. 

Of  the  Organization  of  the  Osseous  Texture. 

Q,   What  is  the  texture  peculiar  to  the  osseous  system? 
23 


178  OSSEOUS    SYSTEM, 

*fl.  It  is  fibrous.  The  fibres  being  differently  arranged 
so  as  to  constitute  the  loose  or  cellular,  and  the  compact, 
bony  structure. 

Q.  How  is  the  cellular  bony  structure  formed? 

«/?.  Unknown  in  the  first  periods  of  ossification,  the 
cells  appear  in  consequence  of  the  absorption  of  the  solid 
mass  of  cartilage,  and  in  its  place  are  deposited  by  exha- 
lation transverse  bony  fibres,  which,  by  interlacing  in 
every  direction,  and  no  more  gelatine  being  thrown  out, 
leave  the  cavities  which  are  the  cells  of  bones. 

Q.  Can  you  present  a  clear  illustration  of  your  last  an- 
swer? 

Jl.  The  os  ethmoides  is  at  one  period  a  solid  cartilage, 
but  under  the  laws  and  in  the  process  of  ossification,  the 
interlacing  bony  fibres  are  exhaled,  and  the  cartilage  ab- 
sorbed leaving  cells. 

Q.  Do  the  cells  communicate  with  each  other? 

*#.  Conclusive  experiments  prove  that  the  cells  through- 
out the  interior  of  a  bone  communicate  universally. 

Q.  How  does  the  compact  texture  of  bones  differ  from 
the  cellular  texture  ? 

*#.  The  fibres  of  the  compact  texture  are  in  dense  juxta- 
positipn. 

Q.  How  do  these  compact  fibres  run  in  the  long,  flat, 
and  short  bones? 

*#.  These  bony  fibres  are  longitudinal  in  the  long,  radi- 
ated in  the  flat,  and  run  in  every  direction  in  the  shortbones. 

Q.  Do  the  fibres  of  this  texture,  in  the  apophyses,  pur- 
sue the  same  direction  as  in  the  main  bone? 

«#.  They  do  not;  in  some  apophyses  they  are  longitu- 
dinal, in  others  the  course  is  entirely  irregular. 


OSSEOUS    SYSTEM.  179 

Q.   Are  the  bones  larnellated  in  their  compact  structure  ? 

Ji.  They  are  not.  If  they  exfoliate  in  scales,  it  is  by 
an  abnormal  process,  not  by  the  separation  of  the  natural 
structure;  again,  exfoliation  does  not  always  assume  the 
form  of  scales  or  layers,  for  it  sometimes  takes  place  in  a 
direction  differing  from  the  course  of  the  supposed  layers. 
The  structure  is  one  of  condensed  fibres. 

Q.  What  is  Beclard's  opinion  as  to  the  laminated  struc- 
ture of  the  bones  in  general? 

«#.  He  thinks,  that  from  a  general  view  of  experiments, 
that  the  structure  is  laminated,  connected  with  fibres,  and 
with  small  areolated  spaces  abounding  between  laminated 
fibrous  structure. 

Q.   How  does  a  bone  become  affected  with  rachitis? 

*#.  In  some  degree  by  the  absorption  of  the  phosphate 
of  lime,  perhaps  too  by  a  diminished  exhalation  of  it; 
but  this  diseased  state  arises  principally  from  a  separation 
of  the  osseous  fibres  from  each  other,  by  which  a  cellular 
instead  of  a  compact  bony  texture  is  formed. 

Q.  What  is  the  usual  general  arrangement  of  the  spongy 
and  compact  texture  of  the  bones? 

«#.  The  compact  texture  is  the  exterior,  and  the  cellu- 
lar the  interior  part  of  the  bone. 

Q.   Is  there  no  exception  to  this  rule? 

•ft.  It  is  inverted  in  the  case  of  the  spongy  bones  of  the 
nose. 

Q.  Where  is  the  compact  texture  of  the  long  bones 
greatest? 

.#.  It  is  greatest  in  the  middle  of  the  bones. 

Q.  And  why.  is  it  so  ? 

«#.  That  it  may  give  solidity  to  the  bones,  and  enable. 


180  OSSEOUS    SYSTEM. 

them  to  resist  fractures  where  they  are  most  exposed  to 
them,  and  that  the  size  of  the  bone  may  be  reduced,  where 
such  reduction  is  necessary,  without  injuring  its  strength. 

Q.  What  is  the  reticular  texture  of  the  bone? 

«/#.  It  is  a  delicate  modification  of  the  cellular  texture; 
and  it  supports  the  medullary  texture  of  the  bones,  and 
offers  points  of  insertion  to  the  membrane  of  the  medulla. 

Q.  How  is  a  light  cellular  structure  at  the  ends  of  the 
bones  advantageous? 

•/#.  The  weight  of  heavy  compact  structure  at  the  ends 
of  the  levers  would  be  difficult  to  raise,  and  thereby  im- 
pede locomotion. 

Q.  Where  are  the  compact  and  cellular  structures  found 
in  the  flat  bones? 

«/?.  The  compact  is  in  the  centre,  the  cellular  is  at  the 
periphery. 

Q.  What  texture  prevails  in  the  short  bones? 

«#.  The  cellular  structure  principally  forms  them. 

Q.  Of  what  do  the  osseous  protuberances  consist? 

«#.  Principally  of  compact  texture. 

Q.  What  are  the  elements  which  enter  into  the  com- 
position of  the  osseous  texture? 

t/?.  A  calcareous  and  gelatinous  substance. 

Q.  What  is  this  calcareous  substance? 

«/?.  It  is  the  phosphate  of  lime;  and  there  are  a  few 
other  unimportant  saline  matters  that  enter  into  the  com- 
position of  bone. 

Q.  Is  the  proportion  of  the  constituent  parts  of  bony 
structure  uniform  ? 

«/?.  It  is  not;  on  the  contrary,  it  varies  much.  The  teeth 
have  much  more  earthy  substance  than  other  bones. 


OSSEOUS    SYSTEM. 


181 


Q.  Is  the  softer  substance  plire  cartilage  or  gelatine? 

«#.  That  it  is  fibrous  texture  cannot  be  doubted ;  it  is 
neither  exclusively  cartilage  nor  gelatine;  the  phosphate 
of  lime  is  deposited  between  these  fibrous  spaces,  and  thus 
constitutes  bone. 

Q.  What  part  of  the  bone  possesses  vitality  and  affords 
nutriment? 

Ji.   The  gelatinous  substance. 

Q.   What  vessels  deposite  the  calcareous  bony  matter? 

«#.   The  red  blood-vessels. 

Q.  Does  a  different  set  of  vessels  deposite  the  gelatine? 

A.   It  is  poured  out  by  white  vessels. 

Q.  What  is  the  aspect  of  osseous  vascularity,  at  different 
periods  of  life? 

«/2.  The  vascularity  of  the  bones  diminishes  with  age, 
and  with  this  diminution  of  vascularity  is  a  corresponding 
declension  in  the  readiness  to  form  callus. 


Of  the  Properties  of  the  Osseous  System. 

Q.   What  are  the  physical  properties? 

«#.  The  bones  are  extremely  solid,  and  hard ;  in  the 
bones  of  young  persons  there  is  slight  elasticity,  which  is 
entirely  lost  in  advanced  life. 

Q.   Do  the  bones  possess  or  exhibit  textural  properties? 

t#.  Bichat  supposes  that  in  spina  ventosa  extensibility 
of  bony  texture  is  manifested ;  and  this  is  also  exhibited 
in  the  distention  of  the  antrum  with  polypus.  On  the 
contrary,  the  alveoli  contract  when  the  teeth  are  removed; 
the  orbit  contracts  when  a  cancerous  eye  has  been  re- 
moved. 


182  OSSEOUS    SYSTEM. 

Q.   What  are  the  vital  properties  of  the  bones? 

+3.  They  have  no  animal  sensibility  in  health,  but  ma- 
nifest it  in  very  great  degree  in  disease.  They  have  no 
animal  contractility;  they  are  destitute  of  sensible  organic 
contractility.  One  would  scarcely  admit  an  insensible  or- 
ganic contractility  in  the  firm  structure  of  bones. 

Q.  On  what  does  the  vitality  of  the  osseous  tissue  de- 
pend? 

«/?.  It  is  dependant  on  organic  sensibility  and  insensible 
organic  contractility.  These  two  properties  they  certainly 
possess. 

Q.  What  influence  has  the  obscurity  of  the  osseous  vital 
properties  on  the  diseases  of  that  texture  ? 

t/2.  The  vital  properties  of  the  bones  are  slow  in  the 
production  and  prosecution  of  diseased  action. 

Q.  There  are  two  sets  of  symptoms  in  all  acute  diseases, 
what  are  they  ? 

«/?.  Those  that  relate  to  the  affected  organ,  and  those 
that  sympathetically  connect  this  organ  with  the  vital 
forces  of  other  parts. 

Q.  Are  the  bones  readily  acted  on  by  the  vital  forces 
of  other  organs? 

«/?.  They  are  not;  they  remain  unaffected.  Their  vitality 
does  not  admit  of  the  sudden  alterations  in  acute  diseases. 

Q.  In  what  part  of  the  osseous  tissue  are  the  vital  pro- 
perties seated? 

«/#.   In  the  cartilaginous  or  gelatinous  substance. 

Q.  What  produces  a  morbid  brittleness  in  the  bones? 

«#.  A  deposition  of  phosphate  of  lime,  in  quantity  dis- 
proportioned  to  the  gelatiiie. 


OSSEOUS    SYSTEM.  183 


Articulations  of  the  Osseous  System. 

Q.  How  are  the  general  classes  of  articulations  divided? 

Jl.  Into  those  with,  and  those  without  mobility. 

Q.  To  what  purposes  are  the  articulations  with  mobility 
directed? 

Jl.  They  belong  to  the  bones  of  locomotion. 

Q.  Where  are  those  without  mobility  found? 

*ft.  In  the  bones  whose  union  forms  cavities  to  defend 
the  important  organs. 

Q.  What  motions  do  the  articulations  with  mobility 
allow  ? 

•ft.  There  are  four  motions,  viz.  of  opposition,  circum- 
duction,  rotation  and  sliding. 

Q.  What  do  you  understand  by  the  motion  of  opposi- 
tion? 

«#.  It  is  simple  flexion  and  extension — abduction  and 
adduction. 

Q.  What  is  the  motion  of  circumduction? 

A.  Circumduction  is  a  movement  in  which  the  bone 
describes  a  kind  of  cone,  the  apex  of  which  is  in  the  su- 
perior articulation,  and  the  base  in  the  inferior.  Circum- 
duction comprises  all  the  motions  of  opposition. 

Q.  How  does  rotation  differ  from  circumduction? 

«#.  In  this,  that  in  circumduction  the  bone  has  loco- 
motion, in  rotation  there  is  none;  in  rotation  the  bone 
turns  on  its  own  axis. 

Q.  What  is  the  sliding  articulation? 

A.  It  is  a  motion  appertaining  to  all  the  articulations, 
and  one  described  by  the  term. 


184  OSSEOUS    SYSTEM. 

Q.  What  indicates  the  disposition  to  luxation  in  an  ar- 
ticulation? 

«/?.  The  number  and  freedom  of  its  motions. 

Q.  What  articulations  afford  extension,  opposition,  cir- 
cumduction,  and  rotation? 

•ft.  The  humerus  and  scapula,  the  femur  and  ilium. 

Q.  What  advantages  arise  from  the  location  of  these 
extensive  motions  at  the  upper  part  of  the  extremity? 

tfl.  The  joints  are  less  exposed  to  accident  and  luxation; 
the  powers  of  motion  being  located  in  the  superior  articu- 
lations, the  whole  limb  has  extensive  motion,  thereby 
making  up  for  the  necessarily  limited  motion  of  the  joints 
below. 

Q.  What  form  of  articulating  surfaces  is  necessary  for 
these  extensive  motions? 

./?.  That  the  receiving  surface  should  be  concave,  and 
the  moveable  one  convex. 

Q.  What  are  the  principal  differences  between  the  mo- 
tions of  the  humeral  and  femoral  articulations? 

«/2.  In  the  humeral  there  is  much  circumduction,  but 
little  rotation;  in  the  femoral  there  is  much  rotation,  but 
little  circumduction.  There  is  pronation  and  supination 
for  the  hand  to  compensate  for  the  want  of  rotation  in  the 
humeral  articulation;  while  the  rotation  of  the  femoral  ar- 
ticulation renders  pronation  and  supination  unnecessary, 
in  the  lower  extremity. 

Q.  On  what  principle  in  the  mechanical  arrangements 
of  the  articulations,  does  the  facility  of  circumduction  de- 
pend? 

*ft.  It  depends  on  the  "  axis  of  the  bone,  and  that  of  the 
motion  being  the  same,"  as  is  seen  in  the  humeral  articu- 


OSSEOUS    SYSTEM. 


185 


lation,  where  there  is  much  circumduction.  The  circum- 
duction  of  the  femur  is  impeded  by  the  distance  of  the 
axis  of  motion  from  that  of  the  bone  being  the  whole 
length  of  the  neck  of  the  thigh  bone. 

Q.  Give  examples  of  articulations  in  which  opposition 
and  circumduction  are  alone  met  with. 

Jl.  In  the  angle  of  the  jaw  is  a  conspicuous  one;  you 
see  others  in  the  wrist  and  radius,  in  the  first  phalanges. 

Q.  Mention  instances  of  the  motion  of  opposition  con- 
fined to  one  direction,  without  circumduction  and  rotation. 

A.  The  knee,  the  elbow,  second  phalanges  of  the  fin- 
gers. These  articulations  are  found  in  the  middle  joints 
of  limbs, 

Q.  What  conformation  marks  these  articulations  of 
opposition,  without  circumduction  or  rotation? 

A.  Prominences,  such  as  condyles  on  the  articular  sur- 
faces j  or  eminences  and  cavities  fitted  for  each  other; 
these,  with  some  other  arrangements,  prevent  other  mo- 
tions than  those  just  mentioned.  These  articulations  are 
remarkable  for  breadth  of  surface. 

Q.  Why  are  luxations  of  these  articulations  more  dan- 
gerous than  others? 

<ft.  Because  so  many  bands  and  ligaments  are  torn  up 
in  their  dislocation. 

Q.  On  what  side  is  there  the  greatest  motion  in  these 
articulations? 

«#.  On  that  of  flexion;  hence  the  strength  of  the  flexor 
fibres,  and  also  the  location  of  the  nerves  and  vessels  for 
security. 

Q.  Can  you  give  examples  of  articulation  with  rotatory 
motion  alone? 

24 


186  OSSEOUS    SYSTEM. 

*#.v  The  ulna  with  the  radius  rotates  only,  the  atlas 
with  the  dentatus;  in  these,  luxation  is  very  difficult. 

Q.  Where  do  you  find  the  articulations  with  sliding 
motion  alone? 

<ft.  They  are  very  numerous;  the  vertebra?  on  each 
other;  the  carpus  and  metacarpus;  the  tarsus  and  meta- 
tarsus; the  sternal  end  of  the  ribs. 

Q.  What  do  you  mean  by  the  immoveable  articulations? 

Ji.  Those  where  surfaces  of  juxta-position  are  so 
wedged  in  as  to  retain  the  part;  as  the  malar  bone  con- 
fined between  several  other  bones  of  the  face.  There  is 
an  order  of  indented  articulations  immoveable  as  by  suture; 
there  is  another  with  implanted  surfaces,  as  the  teeth. 

Q.  What  effect  has  age  on  the  articulation  by  suture? 

./?.  It  obliterates  the  suture  by  bony  union. 

Q.  Why  do  not  the  teeth  unite  to  their  sockets  by 
age? 

«#.  Because  there  is  an  intervening  mucous  membrane 
not  disposed  to  ossify.  The  teeth  constitute  the  only  or- 
der with  implanted  surfaces. 

Q.  What  preserves  the  union  of  the  immoveable  articu- 
lations? 

.#.  Cartilages  and  membranes.  The  cartilages  are 
most  conspicuous  in  infancy. 

Q.  How  are  the  moveable  articulations  united? 

Jl.  By  ligaments  and  muscles;  these  bonds  of  union  are 
freer  in  youth  than  age. 

Q.  How  does  the  office  of  cartilage  differ  in  the  im- 
moveable and  moveable  articulations  ? 

Jl.  It  is  a  bond  of  union  in  the  first,  and  facilitates  mo- 
tion in  the  second, 


OSSEOUS'  SYSTEM,  187 


Development  of  the  Osseous  System. 

Q.  At  what  period  is  ossification  complete  ? 

*#.   From  the  eighteenth  to  the  twentieth  years. 

Q.  What  are  the  states  of  the  bones  during  growth? 

«#.  There  are  the  remarkable  states  of  the  osseous  tex- 
ture; viz.  the  mucous,  the  cartilaginous,  and  the  osseous. 

Q.  At  what  period  do  you  see  the  mucous  state? 

A.  It  appears  in  the  earliest  periods  of  the  development 
of  the  embryo,  and  continues  till  the  vessels  commence 
conveying  gelatine.  The  cartilaginous  state  succeeds  this, 
and  finally  the  deposition  of  phosphate  of  lime  takes  place. 

Q.  What  is  the  first  indication  of  calcareous  deposition? 

«#.  The  appearance  of  red  blood  in  the  cartilaginous 
bed  of  the  bone.  This  blood  enters  vessels  which  formerly 
conveyed  gelatine.  There  is  always  in  the  process  of 
earthy  exhalation  a  red  layer  which  is  vascular,  between 
the  cartilage  and  that  portion  of  the  bone  where  calcare- 
ous deposition  has  taken  place. 

Q.  Why  do  the  vessels  which  once  conveyed  white 
fluids,  afterwards  admit  red  blood  ? 

«/2.  Such  is  the  fact  in  the  deposition  of  calcareous  mat- 
ter in  ossification,  and  it  proceeds  from  a  change  in  the 
relation  of  the  vital  forces  of  the  vessels  to  the  fluids,  re- 
ceiving at  one  time  white,  at  another  red  fluids. 

Q.   At  what  period  does  the  osseous  state  commence? 

«/?.  It  appears  first  in  the  clavicle,  the  ribs,  &c.  about 
the  end  of  the  first  month. 

Q.  Where  do  the  long  bones  increase  in  length? 

•/?.  Only  at  the  extremities,  not  in  the  middle.    An  ac- 


188  OSSEOUS    SYSTEM. 

curate  experiment,  made  by  Mr.  Hunter,  proves  this;  he 
bored  holes  in  the  middle  of  a  long  bone,  and  although 
the  bones  had  grown  considerably  longer,  the  holes  were 
no  farther  apart. 

Q.  In  what  way  does  a  bone  grow  after  the  twentieth 
year? 

«#.  It  grows  in  thickness.  Observe  the  difference  in  a 
thigh  bone  eighteen  years  old  and  one  of  forty. 

Q.  What  evidence  is  there  that  exhalation  and  absorp- 
tion go  on  in  the  bones  ? 

t/2.  The  experiment  of  feeding  with  madder  makes  this 
manifest;  this  colouring  substance  is  alternately  deposited 
and  removed.  It  is  never  coloured  when  gelatine  alone  is 
in  the  bone;  now  this  proves  that  the  calcareous  exhala- 
tion is  the  vehicle  of  it. 

Q.  Can  you,  by  giving  gelatine  or  phosphate  of  lime, 
supply  a  defect  of  these  constituents  in  the  bony  system? 
*#.  No;  unless  you  can  bring  the  organic  sensibility  of 
the  exhalents  of  the  bones  in  due  relation  to  the  blood 
containing  these  principles,  the  vascular  system  of  the 
bones  would  reject  it. 

Q.  What  changes  take  place  in  the  bones  of  old  persons? 
J2.  They  become  of  a  grayish  colour,  and  they  are  hea- 
vier in  old  people,  owing  to  the  preponderance  of  calca- 
reous deposition. 

Q.  Beclard  mentions  a  cause  of  the  brittleness  of  bones 
in  advanced  life,  what  is  it? 

*ft.    Usually,  as  the  medullary  canal  enlarges,  so  does  . 
the  exterior  of  the  bone;  but  sometimes,  in  advanced  life, 
the  canal  continues  to  enlarge,  at  the  expense  of  the  thick- 
ness of  the  walls,  and  hence  the  bone  is  more  brittle. 


OSSEOUS    SYSTEM.  189 

Q.  What  organs  are  most  prone  to  take  on  the  process 
of  ossification  in  advanced  life? 

Jl.  Those,  the  nutritive  matter  of  which,  is  habitually 
gelatine,  as  cartilage.  The  exception  to  this  is  the  arterial 
ossifications  which  so  commonly  take  place. 

Q,  How  many  periods  are  there  in  the  development  of 
callus? 

t#.  There  are  three;  the  formation  of  cellular  granula- 
tions, the  change  of  these  granulations  to  the  cartilagin- 
ous state,  and  the  deposition  of  bone  or  calcareous  sub- 
stance. 

Q.  What  prevents  the  union  of  broken  bones? 

«/?.  Such  frequent  motion  of  the  ends  of  the  broken 
bones,  as  prevents  the  union  of  the  parenchymas  of  nutri- 
tion. 

Q.  Why  is  union  more  difficult  in  a  compound  frac- 
ture? 

«/#.  Because  the  process  of  suppuration  wastes  the  nu- 
tritive restorative  matter. 

Q    Of  what  are  the  teeth  composed? 

\fr.  Of  enamel,  of  ordinary  bone,  and  a  cavity  con- 
taining a  spongy  substance,  with  which  we  are  unac- 
quainted. 

Q.  What  experiment  proves  the  difference  between  the 
enamel  and  the  ordinary  bony  substance  of  the  teeth  ? 

.#.  Diluted  nitric  acid,  while  it  softens  both  portions, 
whitens  the  enamel,  and  renders  the  osseous  portion  yel- 
low. 

Q.   Is  the  enamel  an  organized  substance? 

*&.  While  it  has  sensibility  to  external  impression,  it 
does  not  take  on  diseased  action;  it  is  neither  absorbed 


190  OSSEOTTS    SYSTEM. 

nor  re-deposited;  on  the  whole,  the  question  is  by  no  means 
a  settled  one. 

Q.  What  vital  property  is  conspicuous  in  the  mem- 
brane of  the  teeth  ? 

t/2.   Animal  sensibility  to  a  most  acute  degree. 
Q.  What  sympathies  are  excited  by  diseases  of  the 
teeth? 

«#.  Those  of  animal  sensibility,  and  of  animal  contracti- 
lity.    The  first  is  exemplified  in  the  pains  of  the  teeth ; 
the  second  in  the  convulsions  produced  by  teething. 
Q.   Present  examples  of  the  organic  sympathies. 
Ji.  Those  of  sensible  organic  contractility,  such  as  vo- 
miting, purging,  and  increased  frequency  of  the  heart's 
action.  You  see  those  of  organic  sensibility  and  of  insensi- 
ble organic  contractility  in  the  profuse  salivary  discharges 
from  dentition,  and  other  tooth  affections;  you  see  them 
likewise  in  the  swellings  of  the  face. 

Q.  How  do  the  teeth  usually  sympathize  with  each 
other? 

<fl.  They  sympathize  in  the  frequent  affections  of  cor- 
responding teeth,  on  the  opposite  sides  of  the  face. 

Q.  To  what  tissue  does  the  membrane  lining  the  tooth 
belong? 

*#.  It  is  serous;  as  evidenced  by  its  appearance,  by  its 
having  the  double  night-cap  fold,  and  by  the  fluid  exhaled 
from  it. 

Q.  How  is  formation  of  the  bony  part  of  the  tooth  con- 
ducted? 

«#.  In  layers,  as  it  were,  from  without  inward.  This 
is  done  for  the  protection  of  the  outer  part  of  the  tooth, 
as  that  part  is  first  exposed  to  the'contact  of  foreign  bodies. 


OSSEOUS    SYSTEM.  191 

Q.   How  do  you  account  for  double  rows  of  teeth? 

A.  The  temporary  set  are  not  removed ;  the  permanent 
take  another  direction,  usually  an  internal  one,  appearing 
as  an  inner  row  of  teeth. 

Q.  Do  the  sesamoid  bones  lie  in  the  direction  of  the  ex- 
tension or  flexion  of  a  joint? 

*fl.  In  all  cases  in  the  flexures  of  the  joints,  except  in 
the  instance  of  the  patella. 

Q.  What  is  remarkable  in  the  structure  of  these  bones  ? 

£.  Their  fibro-cartilaginous,  and  fibro-osseous  state. 

Q.  Where  are  they  most  numerous  and  conspicuous? 

«#.  In  the  lower  extremities;  and  they  are  not  seen  in 
any  part  of  the  bones  of  the  trunk. 

Q.  Where  are  they  exclusively  developed? 

t#.  In  the  fibrous  organization,  as  in  the  tendons  or 
ligaments. 

Q.  Do  you  mean  to  say  that  in  their  most  complete 
state  of  ossification,  the  sesamoid  bones  are  partly  fibrous? 

A.  They  are;  for  the  tendinous  fibres  on  the  upper  and 
lower  side  of  these  bones  so  penetrate  its  osseous  sub- 
stance, as  to  be  continuous. 

Q.  At  what  age  are  they  most  numerous? 

*#.   They  are  found  in  greatest  number  in  advanced  life. 

Q.  In  their  union  after  fracture,  how  do  they  differ 
from  other  bones? 

.#.  They  differ  in  the  interposition  of  a  kind  of  fibro- 
cartilaginous  substance,  or,  as  it  has  been  termed,  ligament, 

Q.  In  what  disease  have  they  been  seen  remarkably 
developed  ? 

*#.  In  gout. 


192  OSSEOUS    SYSTEM, 


OF  THE  MEDULLARY  SYSTEM  OF  THE  BONES. 

Q.  Is  there  a  membrane,  or  what  may  be  termed  an  in- 
ternal periosteum,  in  the  osseous  cells. 

*ft.  Bichat  thinks  not;  but  supposes  the  medulla  to  be 
exhaled  by  a  vascular  net-work. 

Q.  What  part  of  the  osseous  medullary  system  possesses 
animal  sensibility? 

*#.  That  vital  property  is  found  only  in  the  middle  of 
the  long  bones.  The  same  part  of  the  system  possesses 
extensibility  and  contractility  of  texture. 

Q.  Where  are  the  pains  usually  ascribed  to  the  bones 
themselves,  really  seated? 

«/?.  In  the  medullary  texture  in  the  middle  of  the  long 
bones. 

Q.  How  is  the  medullary  system  divided? 

A.  .There  is  the  medullary  system  of  the  ends  of  the 
long  bones;  that  of  the  short  and  flat;  and  that  of  the  mid- 
dle of  the  long  bones. 

Q.  In  what  interesting  particular  does  the  medullary 
system  of  the  middle  of  the  long  bones  differ  from  the 
others  ? 

*#.  In  this,  that  the  vital  forces  of  that  system  are  much 
more  active  than  in  those  of  the  short  and  flat  bones,  or 
even  in  the  ends  of  the  long  bones. 

Q.   Is  the  marrow  altered  in  diseases? 

A.  In  some  chronic  affections  it  becomes  mucilaginous 
or  gelatinous,  resembling  in  many  respects  foetal  marrow 
in  which  there  is  no  fat. 

Q.  What  do  you  mean  by  internal  necrosis? 

•fl.  The  destruction  of  the  medullary  substance  of  the 


OSSEOUS    SYSTEM.  193 

bone,  in  which  case  the  periosteum  assumes  the  position 
of  nutritive  parenchyma  in  which  osseous  matter  is  depo- 
sited. 

Q.  Is  there  in  reality  any  marrow  in  the  foetus? 

<fi.  Beclard  says  there  cannot  be,  because  there  is  no 
medullary  membrane. 

Q.  Have  the  medullary  membrane,  or  the  marrow  any 
agency  in  producing  the  synovia? 

Ji.  They  have  not:  for  you  may  destroy  the  medullary 
membrane,  and  still  the  formation  of  synovia  continue 
uninterrupted;  again,  the  marrow  is  in  greatest  abundance 
in  those  parts  of  the  bone  most  remote  from  the  synovia: 
lastly,  in  children,  where  there  is  no  marrow,  synovia 
abounds. 

Q.  What  is  spina  ventosa? 

*2.  Beclard  says  it  is  a  true  cancer  of  the  medullary 
membrane. 


PATHOLOGY  OP  THE  OSSEOUS  TISSUE. 

Q.  What  are  the  diseases  of  the  osseous  tissue? 

«#.  Inflammation,  caries,  necrosis,  exostosis,  osteo-sar- 
coma,  fragility,  and  rachitis. 

Q.  What  gives  peculiar  aspect  to  the  diseases  of  the 
bones? 

A.  The  feebleness  in  their  vital  forces. 

Q.   Give  an  example  of  healthy  osseous  inflammation  ? 

•ft.  You, have  it  in  the  process  of  reuniting  a  fractured 
bone. 

Q.  What  is  caries  ? 

25 


194  OSSEOUS    SYSTEM. 

•ft.  It  is  a  chronic  inflammation  of  the  bones. 

Q.  How  does  necrosis  differ  from  caries  ? 

£.  In  necrosis  the  hone  is  dead,  in  caries  it  is  in  dis- 
ease. 

Q.  What  bones  are  most  liable  to  caries? 

•#.  The  spongy  bones. 

Q.   How  many  forms  are  there  of  exostosis  ? 

«#.  There  is  one  form  in  which  the  enlarged  bone  is 
perfectly  hard,  another  in  which  the  exostosis  is  lamellat- 
ed,  and  a  third  in  which  there  is  a  mixture  of  fleshy  gra- 
nulations sprouting  from  the  bony  disease. 

Q.  What  is  remarkable  of  the  hard  exostosis? 

»/?.  That  the  affection  of  the  soft  parts  bears  no  propor- 
tion to  the  extent  of  the  ossification. 

Q.  What  bones  are  most  liable  to  exostosis? 

•fl.  The  cranium  and  tibia.  You  often  see  them  on  the 
inside  of  the  head  and  in  the  pelvis. 

Q.  Is  there  resolution  or  suppuration  in  exostosis? 

«#.  In  the  hard  and  lamellated  there  are  neither;  but 
the  carneous  exostosis  accompanies  caries,  arid  this  is  vas- 
cular, and  there  is  the  termination  of  the  inflammation  in 
suppuration. 

Q.  To  what  is  the  fragile  bone  or  brittleness  owing  ? 

»#.  To  a  deficiency  of  gelatine. 

Q.  What  is  the  pathology  of  rickets  ? 

A.  It  is  a  deficiency  of  calcareous  deposition. 

Q.  How  is  osseous  malformation  jdivided? 

«#.  Into  congenital  and  accidental. 


OSSEOUS    SYSTEM.  195 


Of  the  Medullary  System. 

Q.  What  is  the  disease  of  this  tissue? 
A.  That  which  is  usually  termed  spina  ventosa. 
Q.  What  is  spina  ventosa? 

A.  It  is  a  "  tumour  arising  from  the  clevelopment  of  the 
bone  and  increase  of  its  fleshy  granulations." 
Q.  Where  is  spina  ventosa  never  known? 
A.  It  is  never  found  in  the  short  flat  bones. 


(     196     ) 


CARTILAGINOUS  SYSTEM. 

Q.  How  is  this  divided? 

«#.  Into  the  cartilaginous  and  nbro-cartilaginous  tissues. 
Q.  What  do  you  mean  by  cartilage? 
•ft.  It  is  a  substance  characterized  by  hardness,  white- 
ness, elasticity,  apparently  but  not  actually  inorganic, 

Forms  of  the  Cartilaginous  System. 

Q.  What  are  the  three  classes  of  cartilages? 

A.  Those  at  the  ends  of  the  moveable  bones,  those  at 
the  union  of  the  immoveable  bones,  -those  on  the  parietes 
of  cavities,  as  the  ribs  and  nose. 

Q.  What  utility  results  from  cartilages  at  the  moveable 
joints? 

•ft.  By  the  properties  of  suppleness,  elasticity,  and 
yielding,  they  increase  the  facility  and  extent  of  the  mo- 
tions of  the  joints,  while  they  break  by  yielding  a  little, 
the  violence  of  the  shocks  the  limbs  experience. 

Q.  Is  the  nutritive  parenchyma  of  the  bone  continued 
into  the  cartilage  ? 

*ft.  No;  they  are  different,  or  rather  distinct. 

Q.  Why  are  the  cartilages  at  the  ends  of  the  moveable 
joints  more  polished  and  shining  than  those  elsewhere? 

./?.  The  extension  of  the  synovial  membrane  over  those 
joints  communicates  that  shining  appearance. 

Q.  Do  you  recollect  any  instances  of  cartilages  in  the 
immoveable  articulations? 


CARTILAGINOUS    SYSTEM.  197 

A.  Those  in  the  sutures  of  the  head,  and  those  in  the 
bones  of  the  face. 

Q.  In  what  respect  do  the  cartilages  in  the  moveable  and 
immoveable  joints  differ? 

»#.  In  the  tendency  of  the  cartilages  of  the  immoveable 
joints  to  ossification,  particularly  those  of  the  sutures  of 
the  head. 

Organization  of  the  Cartilaginous  System. 

Q.  What  is  the  peculiar  organization  of  cartilage  ? 

«/#.  It  is  an  intensely  dense  interlacing  of  fibres,  longi- 
tudinal and  transverse. 

Q.  Is  cartilage  disposed  to  putrescency? 

A.  It  resists  putrefaction  longer  than  any  part,  except 
bones. 

Q.  What  change  takes  place  in  disease  ? 

Jl.  It  becomes  in  some  instances,  as  in  hip  disease, 
soft,  lardaceous,  and  vascular.  Sometimes  it  is  even  os- 
seous, and  then  medullary  cavities  are  formed  and  fluid 
deposited. 

Q.  Bichat  mentions  another  remarkable  change  of  the 
cartilaginous  tissue  in  disease,  what  is  it? 

«#.  In  two  instances  he  saw  the  cartilages  of  the  hip 
and  thigh  bones  converted  into  a  substance  like  ivory. 

Q.  What  is  the  common  organization  of  cartilage? 

•#.  Cellular  substance,  and  in  health  white  fluids,  exha- 
lents  and  absorbents.  In  disease  red  fluids  are  conveyed; 
in  jaundice  the  cartilages  become  very  yellow.  No  nerves 
have  been  found  in  cartilages. 

Q.  What  proves  the  existence  of  cellular  texture  in 
cartilage? 


198  CARTILAGINOUS    SYSTEM. 

) 

»3.  The  granulations  in  wounds  of  this  tissue,  besides 
other  evidences,  particularly  the  spongy  appearances  in 
diseased  cartilage. 

Properties  of  the  Cartilaginous  System. 

Q.  What  physical  property  is  most  eminently  possess- 
ed by  cartilage? 

.#.  Elasticity,  and  this  is  greatest  in  adults. 

Q.  Where  are  cartilages  placed,  and  what  general  prin- 
ciples govern  their  location? 

*ft.  They  are  placed  where  a  peculiar  union  of  physical 
properties  as  well  as  vital  forces  are  necessary  to  the 
functions  of  parts. 

Q.  What  elementary  constituent  contributes  mainly  to 
the  elasticity  of  parts  of  the  body  ? 

•ft..  Perhaps  it  is  more  owing  to  the  proportion  of  gela- 
tine than  to  any  thing  else. 

Q.  Are  the  properties  of  texture  much  developed  in 
cartilage  ? 

JL.  Extensibility  and  contractility  are  scarcely  observa- 
ble in  cartilage. 

Q.  What  vital  properties  belong  to  cartilage? 

*#.  The  functions  of  cartilage  imply  insensible  organic 
contractility  and  organic  sensibility.  Animal  sensibility 
is  developed  only  in  their  diseases.  Animal  contractility 
is  foreign  from  them.  Sympathies,  either  active  or  passive, 
are  inoperative  with  cartilages. 

Q.  What  then  is  the  general  character  of  the  vital  pro- 
perties of  cartilage  ?  , 

•#.  It  is  that  they  are  slow  in  operation,  and  obscure  in 
existence;  and  consequently  their  diseases  are  chronic. 


CARTILAGINOUS    SYSTEM.  199 

Q.  What  important  consideration  does  the  general  cha- 
racter of  the  vital  forces  of  various  parts  inculcate  on  the 
pathologist? 

*ft.  That  these  forces  are  exceedingly  various  in  differ- 
ent tissues.  Active  in  some,  their  diseases  are  acute  and 
rapid,  and  their  restoration  speedy.  Slow  in  others,  their 
diseases  are  chronic,  and  their  reunion  very  tardy.  And 
again,  that  acute  and  chronic  inflammation  are  relative, 
not  arbitrary  terms;  governed  in  their  application  by  the 
activity  of  the  vital  forces  of  the  part. 

Development  of  the  Cartilaginous  System. 

Q.  What  constitutes  the  mucous  bed  of  the  osseous  and 
cartilaginous  systems  in  the  foetus? 

A.  The  cellular  and  vascular  parenchyma;  this  is  after- 
wards penetrated  by  the  peculiar  saline  and  gelatinous 
substances,  which  form  the  bone  and  cartilage. 

Q.  What  effect  has  age  on  the  deposition  of  gelatine? 

£.  It  diminishes  as  we  advance  in  life;  young  animals 
yield  the  most  jelly. 

Q.  What  appearances  take  place  in  macerating  the  car- 
tilages of  young  animals  in  water? 

£.  They  become  of  a  reddish  colour. 

Q.  It  has  been  said  that  the  motions  of  the  cartilages  in 
the  moveable  articulations  prevents  their  ossifications; 
may  not  another  physiological  reason  be  given  for  this? 

«#.  In  the  moveable  articulations  the  organic  sensibility 
of  the  cartilage  not  being  in  relation  to  the  red  blood'  and 
.calcareous  substance,  they  are  neither  conveyed  to  the 
cartilage  nor  deposited  in  it;  hence  ossification  does  not 
take  place. 


200  CARTILAGINOUS    SYSTEM. 

Q.  What  change  is  manifested  in  the  cartilages  at  ad- 
vanced periods  of  life? 

Ji.  They  become  ossified  in  many  cases. 

Q.  What  does  the  early  tendency  of  the  cartilages  of 
the  cavities  to  ossification  often  induce? 

•ft.  More  frequent  caries  of  these  than  of  other  carti- 
lages. 

Q.  What  laryngeal  cartilages  are  most  disposed  to 
ossify? 

*#.  The  arytenoid;  in  every  case  of  laryngeal  phthisis 
this  has  appeared  on  dissection. 

Q.  What  different  causes  give  rise  to  osseous  and  carti- 
laginous depositions,  where  these  should  not  be? 

•ft.  Age  produces  the  bony  deposition;  disease  gives  rise 
to  the  cartilaginous  formations. 

Q.  Where  is  preternatural  cartilage  most  frequently 
found? 

«#.  In  the  spleen  and  in  the  lungs. 

Q.  What  is  the  composition  of  the  cartilages? 

»#.  Varying  in  the  constituent  proportions  at  different 
periods  of  life,  they  are  composed  of  albumen,  mucus, 
oil,  acetic  acid,  water,  phosphate  of  lime,  and  other  salts. 

Q.  What  is  the  morbid  anatomy  of  the  cartilages? 

«#.  Swelling  and  softness  in  white  swelling;  they  are 
sometimes  absorbed  or  converted  to  bone;  they  ulcerate. 
When  broken  they  reunite  by  means  of  bony  bands  and 
bonds. 


(    201     ) 


FIBROUS  SYSTEM. 

Of  the  Forms  and  Divisions  of  the  Fibrous  System. 

Q.   How  are  the  fibrous  forms  divided? 

«#.  Into  membranes  and.  fasciae. 

Q.  How  are  the  fibrous  organs  of  a  membranous  form 
arranged? 

Jl.  Into  the  orders  of  fibrous  membranes,  fibrous  cap- 
sules, fibrous  sheaths,  and  into  aponeuroses. 

Q.   Give  some  examples  of  the  fibrous  membranes. 

Jl.  You  see  them  in  the  periosteum,  dura  mater,  the 
sclerotica,  albuginea,  the  peculiar  membrane  of  several 
organs,  as  the  spleen  and  kidney. 

Q.  Where  are  the  fibrous  capsules  found? 

A.  They  are  met  with  around  the  articulations  of  the 
arm  and  hip,  and  some  others,  and  wherever  found  their 
office  is  to  strengthen  the  joint. 

Q.  What  situations  do  the  fibrous  sheaths  occupy? 

«#.  They  bind  down  the  tendons  as  they  pass  on  the 
bones. 

Q.  How  are  the  fibrous  aponeuroses  divided? 

A.  Into  those  which  are  spread  out  as  coverings  over 
parts,  and  those  which  afford  muscles  places  for  insertion. 

Q.  How  are  the  fibrous  organs  in  form  of  fasciae  di- 
vided ? 

«#.  Into  tendons  and  ligaments. 

Q.  Where  are  tendons  found? 

»#.  At  the  origin,  middle,  or  insertion  of  muscles. 
26 


202  FIBROUS    SYSTEM 

Q.  Where  do  you  meet  with  ligaments? 

•#.  Their  office  being  to  strengthen  the  joints,  they 
are  met  with  about  the  bony  or  cartilaginous  articulations. 

Q.  What  is  the  common  centre  of  the  fibrous  organs? 

Jl.  The  periosteum. 

Q.   Why  is  the  periosteum  thus  considered? 

*#.  Because,  generally  speaking,  the  fibrous  organs  are 
attached  to  the  periosteum. 

Q.  What  are  the  principal  exceptions  to  this  anatomical 
arrangement? 

•   *#.   The  albuginea  of  the  eye,  the  membranes  of  the 
spleen  and  liver. 

Organization  of  the  Fibrous  System. 

Q.  What  is  the  organization  of  the  fibrous  system? 

Jl.  It  is  a  peculiar,  hard,  slightly  elastic  fibrous  base, 
destitute  of  sensibility,  and  nearly  so  of  contractility.  The 
fibres  are,  in  tendons,  in  juxta-position;  they  are  so  like- 
wise in  ligaments.  In  membranes,  the  fibres  are  crossed 
in  every  direction. 

Q.  Is  the  power  of  resistance  in  the  fibrous  system 
great? 

./?.  Sometimes  it  is  even  greater  than  that  of  the  bones, 
as  the  patella.  Recollect  the  violence  requisite  to  draw 
criminals  asunder  by  horses,  in  the  punishments  of  the 
ancients. 

Q.  Why  are  tendons  always  ruptured,  rather  than  the 
muscular  fleshy  fibres? 

»/?.  Because  the  fleshy  fibre  is  in  such  constant  con- 
traction and  approximation,  as  to  enable  the  strength  of 
the  muscle  to  exceed  that  of  the  tendon. 


FIBROUS    SYSTEM. 


203 


Q.  Why  do  you  doubt  the  identity  of  muscular  and 
fibrous  tissues? 

*#.  Those  tissues  cannot  be  alike  which  vary  so  much 
in  chemical  composition,  in  organization,  in  vital  pro- 
perties, and  in  functions. 

Q.  What  portions  of  the  fibrous  system  are  most  liable 
to  inflammation? 

•#.    In  those  where  there  is  most  vascularity. 

Properties  of  the  Fibrous  System. 

Q.  What  physical  properties  belong  to  the  fibrous  sys- 
tem? 

«/?.  Elasticity,  and  that  quite  obscure. 

Q.  Are  there  any  textural  properties  in  this  tissue? 

t#.  Extensibility,  which  takes  place  slowly.  In  their 
extension,  the  fibrous  organs  become  sometimes  thinner 
than  natural,  in  other  cases  they  are  thicker.  Contractility 
is  also  seen  in  these,  and  it  is  as  slow  in  development  as 
the  extensibility. 

Q.  Give  instances  of  the  extension  and  contraction  of 
the  fibrous  system. 

.#.  The  dura  mater  in  hydrocephalus;  the  fibrous  or- 
gans in  the  abdomen  in  pregnancy  and  ascites;  now  in  the 
restoration  of  these  parts  to  their  natural  size,  you  see  the 
contractility  of  the  fibrous  organs. 

Q.  What  are  the  vital  properties  of  this  system? 

,#.  Organic  sensibility  and  insensible  organic  contrac- 
tility; but  animal  contractility,  and  sensible  organic  con- 
tractility do  not  belong  to  it. 

Q.  What  is  the  peculiarity  of  the  animal  sensibility  in 
this  tissue? 


204  FIBROUS    SYSTEM. 

tfl.  It  is  that  ordinary  stimulants  do  not  excite  it.  It 
is  put  in  action  by  violent  extension  or  sudden  distention; 
hence  the  acute  pains  of  straining,  stretching,  or  twisting 
the  joints  or  the  spine.  You  will  also  here  bear  in  mind 
the  severity  of  pain,  when  pus  is  confined  by  an  aponeu- 
rosis. 

Q.  Are  the  vital  forces  of  the  fibrous  system  active? 

«/#.  Much  more  so  than  those  of  the  osseous  and  carti- 
laginous tissues;  but  the  forces  vary  in  different  parts  of  it. 

Q.  What  remarkable  circumstance  is  observed  in  in- 
flammation of  this  system? 

•ft.  That  it  does  not  produce  pus. 

Q.  But  does  not  the  dura  mater  suppurate? 

t/?.  Bichat  says  it  does  not;  that  the  pus  proceeds  from 
the  tunica  arachnoides  on  the  dura  mater. 

Q.  What  sympathies  arise  from  this  fibrous  system  ? 

t#.  They  are  various.  The  animal  sensibility  of  the 
whole  limb  may  be  increased ;  again,  animal  contractility 
of  remote  parts  is  excited  as  in  tetanic  symptoms  from 
wounds,  or  in  the  sardonic  grin  from  punctured  diaphragm. 
At  another  time  you  find  the  organic  sensibility  of  parts 
is  exalted,  as  when  the  pericranium  is  inflamed  from  sym- 
pathy with  the  dura  mater.  The  sensible  organic  contrac- 
tility is  disturbed,  as  when  the  stomach  vomits  from  wound 
of  the  sclerotica,  or  when  the  heart  is  disturbed  by  fibrous 
pain. 

Q.  What  vital  property  in  the  tissues  is  apt  to  be  ex- 
cited by  sympathetic  compressions? 

•#.  The  predominant  vital  force  of  each  system. 


FIBROUS    SYSTEM.  205 

Development  of  the  Fibrous  System. 

Q.  What  consequence  results  from  the  softness  and 
want  of  resistance  in  the  fibrous  systems  of  early  years? 

^.  That  luxations  are  more  rare;  that  sprains  are  less 
violent;  that  the  articulations  are  more  extensible  than  in 
after  life,  when  the  ligaments  are  stiff  and  strong.  The 
weakness  of  the  vital  forces  in  this  tissue  in  infantile  life, 
renders  it  less  liable  to  rheumatism. 

Of  the  Fibrous  Membranes  in  General. 

Q.  How  are  these  distinguishable  from  serous  and. mu- 
cous membranes? 

«#.  The  fibrous  are,  with  one  exception,  exactly  adapt- 
ed to  the  form  of  the  organs  they  cover;  the  exception  is 
the  dura  mater.  The  two  surfaces  of  these  membranes  are 
adherent,  and  they  are  perforated  for  the  passage  of  ves- 
sels. Now,  in  all  these  respects,  they  differ  from  the  serous 
and  mucous  membranes. 

Q.  Is  it  certain  that  the  membrane  of  the  corpus  caver- 
nosum  penis  is  fibrous  ? 

Jl.  Various1  experiments  prove  the  difference  between 
the  membrane  of  the  corpus  cavernosum  penis  and  the 
spongy  textures,  and  substantiate  its  resemblance  to  the 
fibrous  tissues. 

Of  the  Periosteum. 

Q.   For  what  is  the  periosteum  remarkable  in  infancy  ? 

A.  For  its  greater  thickness,  its  feebler  connexion  with 
the  bones,  and  its  softer,  more  spongy,  and  gelatinous  as- 
pect, than  in  after  life. 

Q.  Is  the  periosteum  continued  over  the  articulations? 


206  FIBROUS    SYSTEM. 

../?.  It  is  not.  The  ligaments  intermix  with  it,  serve  as 
a  means  of  communication,  and  thus  is  it  continued. 

Q.  What  bony  parts  are  destitute  of  it? 

-ft.  The  crown  of  the  tooth,  and  the  bony  projections 
on  the  heads  of  animals. 

Q.  What  different  morbid  processes  take  place  when 
the  medullary  substance  and  periosteum  are  diseased  ? 

•ft.  In  the  disease  of  the  medullary  substance,  necrosis 
seizes  the  whole  bone;  in  that  of  the  periosteum,  the  ex- 
ternal laminae  are  alone  affected. 

Q.  What  is  the  direction  of  the  fibres  of  the  perios- 
teum? 

•ft.  It  is  that  of  the  fibres  of  the  long  and  short  bones, 
but  not  radiated  as  the  fibres  of  the  flat  bones  are. 

Q.  Are  the  fibrous  organs  inserted  into  the  periosteum, 
or  are  they  more  immediately  connected  with  the  bone? 

•ft.  In  infancy  they  are  not  connected  with  the  bone; 
but  as  ossification  progresses,  it  attaches  the  inner  layers  of 
the  fibrous  organs,  and  thus  firmly  supports  the  powerful 
action  of  the  muscular  lever. 

Q.  What  are  the  uses  of  the  periosteum  ? 

•ft.  It  protects  the  bones  from  the  action  of  surround- 
ing parts:  it  assumes  the  ossific  process  when  disease 
destroys  the  bones :  by  the  ossification  of  its  inner  layers  it 
increases  the  thickness  of  the  bones:  but  above  all,  it  af- 
fords to  the  fibrous  organs  a  general,  solid,  resisting  sup- 
port 

Of  the  Fibrous  Capsules. 

Q.  Where  are  they  found? 

•ft.  Almost  exclusively  on  the  scapulo-humoral  and 
ilio-fe moral  articulations. 


FIBROUS    SYSTEM.  207 

Q.  Why  are  they  only  found  there? 

A.  Because  these  articulations  having  equal  motion  in 
all  directions,  require,  equal  support  in  all  directions. 

Q.  What  is  the  use  of  the  fibrous  capsules  ? 

•tf.  To  give  strength  to  the  articulations;  they  do  not 
exhale  the  synovia. 

Q.  Are  the  capsules  which  form  around  unreduced 
heads  of  bones  fibrous? 

*ft.  They  are  not;  no  fibres  can  be  traced  in  them — they 
are  serous. 

Of  the  Fibrous  Sheaths. 

Q.  How  are  they  divided? 

A.  Into  partial  and  general. 

Q.  Explain  this  division. 

A.  The  partial  are  attached  to  one  or  two  tendons;  the 
general  confine  or  belong  to  an  assemblage  of  muscles  or 
tendons,  as  at  the  wrist  and  ankle,  where  the  annular  liga- 
ments are. 

Q.  What  muscles  in  the  limbs  have  the  partial  fibrous 
sheaths  ? 

«/2.  Only  the  flexors;  the  extensors  are  destitute  of  them. 
The  reason  of  this  is  the  flexors  require  more  strength  and 
support  than  the  extensors. 

Of  the  Aponeuroses. 

Q.  How  are  the  aponeuroses  divided? 

Ji.   Into  those  for  covering  and  those  for  insertion. 

Q.   How  are  the  aponeuroses  for  covering  sub-divided? 


208 


FIBROUS    SYSTEM. 


.   Into  those  for  general  and  those  for  partial  'cover- 


ing. 


Q.  Where  are  those  for  general  covering  found? 

.#.  Around  the  extremities,  where  they  tie  down  the 
muscles.  These  aponeuroses  are  thick  and  strong  in  pro- 
portion to  the  size  and  action  of  the  muscles  they  cover. 
When  it  is  otherwise,  as  in  the  gastrocnemii  muscles, 
these  muscles  are  liable  to  a  species  of  dislocation  and 
cramp. 

Q.   What  do  you  mean  by  the  tensor  muscles? 

«/?.  They  are  muscles  inserted  into  the  aponeuroses  for 
general  covering,  to  tighten  or  relax  them,  as  the  situa- 
tion of  the  limb  may  require. 

Q.  With  what  tissue  do  these  general  aponeuroses  pe- 
culiarly intermix? 

«/#.  In  some  parts  of  the  limbs  they  are  gradually 
merged  or  lost  in  the  cellular  tissue. 

Q.  What  are  the  uses  of  these  aponeuroses? 

<&.  Besides  confining  the  muscles,  they  by  compression 
favour  the  circulation  of  the  red  and  white  fluids.  Hence 
dropsy  is  rarer  and  later  in  forming  in  the  sub-aponeurotic 
cellular  tissue  than  in  the  superficial. 

Q.  Where  are  the  aponeuroses  for  partial  covering 
found  ? 

«/#.  On  the  hand,  on  the  back  and  abdomen,  some  of 
the  muscles  of  which  they  cover  and  aid. 

Q.  How  are  the  aponeuroses  of  insertion  divided  ? 

A.  Into  those  with  a  broad  surface,  those  in  the  form 
of  an  arch,  and  those  with  separate  fibres.  Those  in  the 
arched  form  are  to  allow  vessels  to  pass  under  them. 


FIBROUS    SYSTEM.  209 

Of  the  Tendons. 

Q.  Are  tendons  active  or  passive  in  their  functions? 

A.  They  are  passive,  being  moved  by  the  muscles. 

Q.  At  which  extremity  of  a  muscle  are  they  usually 
found? 

*ft.  At  that  end  of  the  bone  where  the  motion  is 
greatest. 

Q.  What  are  the  forms  of  the  tendons? 

t#.  Some  are  flat;  most  of  them  are  round;  some  are 
bifurcated.  Their  union  is  exclusively  with  fibrous  mem- 
branes, never  with  serous  or  mucous  membranes. 

Q.   What  is  the  organization  of  the  tendons? 

«#.  They  are  a  union  of  fibres,  connected  by  compact 
cellular  membrane. 

Q.  What  is  the  character  of  their  vital  forces? 

«#.  They  are  very  weak. 

Q.  What  muscles  are  destitute  of  tendons? 

«#.  Those  of  organic  life,  and  nearly  all  those  of  animal 
life,  which  form  the  sphincters. 

Of  the  Ligaments. 

Q.  What  is  the  difference  in  the  attachments  of  the  ten- 
dons and  ligaments  ? 

A.  One  end  of  a  tendon  is  attached  to  a  muscle,  whereas 
both  ends  of  a  ligament  are  attached  to  the  periosteum. 

Q.  How  is  it  that  the  ligaments  execute  a  double  pro- 
perty ? 

«#.  By  strength  they  unite  the  bones,  and  by  flexibility 
they  allow  free  motions. 

27 


210  FIBROUS    SYSTEM. 

Q.   To  what  is  club-foot  owing? 

.#.  To  weakness  and  relaxation  of  the  ligaments. 

Q.  What  changes  does  white  swelling  produce  in  the 
ligaments  and  tendons? 

*#.  A  softening,  thickening,  and  consequent  impotence 
in  these  muscular  and  cuticular  attachments. 

Q.   Is  morbid  fibrous  tissue  ever  produced? 

«#.  Frequently  in  the  uterus,  vagina,  and  other  parts. 

Of  the  Yellow  Elastic  Tissue. 

Q.  What  additional  division  in  the  fibrous  system  does 
Beclard  make? 

Jl.  He  describes  what  he  terms  the  yellow  elastic  tis- 
sue, as  it  is  found  in  man  and  animajs.  It  is  seen  in  the 
vertebrae,  in  the  peculiar  membrane  of  the  arteries,  in  the 
ligamentum  nuchae  of  animals,  and  it  supports  the  abdo- 
minal parietes  of  animals.  It  is  in  the  cat's  claw.  This 
tissue  is  remarkable  for  its  elasticity.  It  is  not  only  in 
the  peculiar  membrane  of  the  arteries,  but  in  that  of  the 
vascular  system  generally. 


PATHOLOGY  OF  THE  FIBROUS  SYSTEM, 

Q.  What  are  the  diseases  of  this  tissue? 

A.  Inflammation;  osseous,  fungous,  cartilaginous,  car- 
cinornatous  transformation;  but  these  are  much  modified 
by  the  portions  of  the  system  affected. 

Q.  Does  rheumatism  affect  the  tendons? 


FIBROUS    SYSTEM.  211 

«#.  It  is  said  not;  the  ligaments  are  its  seats  about  the 
joints;  the  tendons  are  not  painful  in  rheumatism. 

Q.  Is  the  dura  mater  liable  to  inflammation? 

t#.  If  so,  it  is  not  much  disposed  to  it.  Inflammation 
which  has  been  ascribed  to  the  dura  mater  was  really  in 
the  arachnoides. 

Q.  How  do  you  distinguish  periosteal  tumour  from 
exostosis  ? 

&  The  tumour  of  the  periosteum  is  more  painful,  of 
more  rapid  increase,  and  is  softer  than  exostosis. 

Q.  Is  there  much  difference  between  inflammation  of 
the  periosteum  and  spina  ventosa? 

«tf.  In  the  first  the  bony  cylinder  of  periosteum  cases  a 
portion  of  dead  bone;  in  spina  ventosa  the  diseased  and 
healthy  bone  are  continuous. 

Q.  How  does  periosteal  inflammation  terminate? 

A.  It  usually  ends  in  suppuration. 

Q.  But  as  a  general  observation,  how  does  inflamma- 
tion of  the  fibrous  tissue  terminate? 

/I.  In  resolution  or  thickening. 

Q.  How  are  the  cicatrices  of  the  liver  formed  ? 

t#.  They  are  fibrous  adhesions. 


OF  THE  FIBRO-CARTILAGINOUS 
SYSTEM. 

Q.  Where  is  this  found? 

Ji.  In  the  ear,  in  the  alac  of  the  nose,  in  the  trachea,  in 
the  eye-lids.  It  is  found  in  the  spinal  inter-articular  sub- 
stance, in  the  iliac  and  pubic  symphysis,  and  it  appears 
sometimes  as  tendinous  sheaths. 

Q.  Of  what  does  this  system  consist? 

«#.  Of  a  mixture  of  fibrous  and  cartilaginous  substance, 
of  which  the  former  is  the  base. 

Q.   What  are  the  functions  of  this  tissue  ? 

«/?.  It  has  great  power;  it  preserves  the  vertebrae,  knee, 
jaw,  and  other  articular  surfaces  in  place.  It  is  in  most 
instances  destitute  of  perichondrium. 

Q.  Does  any-other  structure  enter  into  the  fibre-cartila- 
ginous tissue,  than  those  indicated  by  its  name? 

A.  It  has  a  little,  very  condensed  cellular  texture.  Few 
blood-vessels,  and  no  nerves  can  be  seen  in  this  texture. 

Q.  What  properties  appertain  to  this  tissue? 

Jl.  The  physical  are  elasticity  and  suppleness  to  a  great 
degree:  observe  these  in  the  spinal  column,  nose  and  ears. 

Q.  What  are  the  textural  properties  of  this  system? 

«#.  Both  extensibility  and  contractility.  The  nose 
dilates  from  tumours  and  polypus,  and  contracts  slowly 
when  the  distention  is  removed. 

Q. .  You  have  frequently  met  with  and  mentioned  clas- 


FIBRO-CARTILAGINOUS    SYSTEM.  213 

ticity,  extensibility,  and  contractility;  how  do  these  pro- 
perties principally  differ? 

e/2.   Elasticity  is  a  rapid,  the  others  are  slow  actions. 

Q.  What  are  the  vital  properties  of  this  tissue? 

»#.  Organic  sensibility  and  insensible  organic  contrac- 
tility ;  and  these  in  a  degree  sufficing  only  for  the  nutri- 
tion of  the  tissue.  Neither  active  nor  passive  sympathies 
are  met  with  here. 

Q.  Have  the  fibro-cartilages  much  disposition  to  ossify  ? 

«#.  Not  near  so  great  as  the  cartilages.  Beclard  accu- 
rately observes  that  there  are  temporary  and  permanent 
fibro-cartilages.  The  first  having  served  their  purposes, 
ossify;  the  second  remain  fibro-cartilaginous. 


("214     ) 


MUSCULAR  SYSTEM. 

Q.   How  is  the  general  muscular  system  divided? 

&.  Into  the  muscular  systems  of  animal  and  organic 
life. 

Q.  In  what  respects  do  these  differ  from  each  other? 

«/?.  They  differ  in  the  vital  forces  which  animate  them-, 
in  their  external  forms  ;  in  their  mode  of  organization  ; 
and  the  parts  they  perform  in  animal  and  organic  life. 

I.  OF  THE  MUSCULAR  SYSTEM  OF  ANIMAL  LIFE. 

Q.  What  are  its  first  conspicuous  characters  ? 

«/?.  The  size  it  attains,  and  space  it  occupies;  and  its 
agency  in,  and  adaptation  to  the  defence  of  the  vital  or- 
gans. 

Of  the  Forms  of  the  Muscular  System  of  Animal  Life. 

Q.  How  are  these  muscles  divided? 
»#.  As  the  bones  are,  into  long,  broad,  and  short  mus- 
cles. 


1.    Of  the  Long  Muscles, 

Q.  Where  do  you  find  these? 

A.   Generally  in  the  limbs. 

Q.  What  external  and  internal  layers  belong  to  them? 


MUSCULAR    SYSTEM.  '  215 

A.  The  aponeurosis  between  them  and  the  skin,  and 
the1  periosteum  between  them  and  the  bones,  form  for  them 
a  fibrous  sheath,  in  which  they  play. 

Q.  Where  are  the  longest  of  these  muscles  ? 

*ft.  The  external  muscles  are  the  longest;  the  deep- 
seated  the  shortest. 

Q.  What  separates  the  muscles  from  each  other? 

«#.  Cellular  layers  are  interposed  between  the  muscles. 

Q.   How  are  the  long  muscles  divided? 

•ft.  Into  the  simple  and  compound.  Composed  of  a  sin- 
gle fasciculus,  they  are  single;  where  fasciculi  unite,  the 
muscles  are  compound. 

Q.  What  purpose  is  served  when  several  of  the  long 
muscles  are  united  by  aponeurosis  ? 

«/2.  The  force  and  direction  of  muscular  power  are 
concentrated. 

2.    Of  the  Broad  Muscles. 

Q.  Where  are  they  generally  found? 

«/?.  Covering  the  parieties  of  the  cavities  of  the  body. 

Q.  What  offices  do  they  perform  ? 

•ft.  Three;  they  in  some  extent  contribute  to  the  forr 
mation  of  the  parietes;  they  protect  the  contained  organs; 
and  aid  these  last  in  the  discharge  of  their  functions  by 
the  motions  they  communicate. 

Q.  Why  is  cramp  never  felt  in  these  broad  muscles? 

t#.  As  cramp  arises  from  the  displacement  of  a  muscle, 
and  as  these  broad  muscles  are  not  liable  to  dislocation, 
they  do  not  suffer  from  cramp. 

Q.  The  circumstance  of  these  broad  muscles  not  being 


216  MITSCITLAR    SYSTEM. 

liable  to  displacement,   accounts  for  an  anatomical  fact, 
what  is  it? 

J2.  They  are  not  often  covered  with  aponeuroses. 


3.    Of  the  Short  Muscles. 


Q.  What  do  you  mean  by  these  ? 

Ji.  They  are  a  class  of  muscles  equal  in  length,  breadth 
and  thickness,  fitted  by  this  formation  for  strong  yet  cir- 
cumscribed motion. 

Q.  Where  are  they  found  ? 

*#.  About  the  shoulder  and  hip  joints;  about  the  jaw, 
the  palm  of  the  hand,  and  so  forth. 


Organization  of  the  Muscles. 


Q.  What  peculiar  organization  is  found  in  muscles? 

«tf.  A  red,  flabby  (molasse)  fibre,  with  uniformity  of 
size  in  the  large  and  small  muscles,  running  its  course 
without  bifurcation.  A  single  fibre  is  not  visible,  but  as 
they  are  always  united  in  a  bundle,  they  are  thus  dis- 
tinctly seen. 

Q.  What  constitutes  general  contraction  of  a  muscle? 

«#.  The  union  of  many  separate,  distinct,  and  indepen- 
dent contractions. 

Q.  What  is  the  direction  of  the  fibres  of  the  voluntary 
muscles  ? 

•#.  Straight,  except  in  the  sphincters. 

Q.  How  does  muscular  texture  differ  from  fibrous? 

*tf.   In  its  softness  and  small  degree  of  resistance. 


MUSCULAR    SYSTEM.  rf         217 

Q.  How  then  is  it  that  muscles  are  so  rarely  ruptured? 

*ft.  Because  the  concentrated  contraction  of  a  great  num- 
ber of  fibres,  compensates  for  the  weakness  of  one. 

Q.  What  is  the  proximate  principle,  the  essence  of  the 
muscular  texture? 

*#.  When  by  various  means  you  have  separated  the  co- 
louring matter,  gelatine,  albumen,  and  saline  principles 
from  the  muscle,  you  will  have  left  a  gray  fibre,  which  is 
not  soluble  in  warm  water,  but  is  so  in  weak  acids.  This 
fibre  gives  out  much  azote  when  exposed  to  nitric  acid, 
and  it  resembles  the  fibrin  of  the  blood.  This  substance 
constitutes  the  nutritive  matter  of  muscles,  as  phosphate 
of  lime  does  that  of  bones. 

Q.  What  relation  does  this  fibrous  substance  bear  to  the 
blood? 

*#.  There  is,  in  general,  a  constant  relation  between  the 
quantity  of  this  fibrous  substance  contained  in  the  muscles, 
and  the  quantity  of  it  that  the  blood  contains. 

Q.  What  organization  is  common  to  the  muscles  and 
other  parts? 

«/?.  Cellular  substance,  which  abounds  greatly,  envelop- 
ing every  muscle,  fasciculus,  and  fibre. 

Q.  What  is  the  use  of  this  cellular  texture  in  the  mus- 
cles? 

Ji.  It  fixes  them  in  their  place,  and  greatly  facilitates 
their  motions. 

Q.  There  is  another  constituent  in  muscular  organiza- 
tion, what  is  it? 

A.   It  is  red  blood  which  enters  largely  into  it. 

Q.  Is  it  the  mere  circulation  of  that  fluid  which  colours 
a  muscle? 

2S 


218  MUSCULAR    SYSTEM. 


./?.  No;  it  is  that  portion  of  it  which  combines  with  the 
peculiar  muscular  texture. 

Q.  Why  do  you  suppose  that  to  be  the  case? 

Jl.  Because  in  asphyxiated  animals  while  black  blood 
circulates,  the  muscular  colouring  substance  does  not  be- 
come black;  and  because  in  many  parts  which  have  mus- 
cular fibres,  red  blood  circulates  freely,  yet  does  not  co- 
lour the  fibres.  It  is  not  the  mere  circulation  of  red  blood 
which  colours  the  fibres.  Another  reason  is  here,  that 
in  some  animals  in  which  red  blood  circulates,  the  muscles 
are  white. 

Q.  In  what  class  of  diseases  do  the  muscular  vessels 
allow  the  escape  of  blood? 

«/?.  In  diseases  of  debility;  never  in  those  of  increased 
activity. 

Q.  Whence  are  the  nerves  of  the  muscles  of  animal  life 
derived  ? 

«/?.  Almost  entirely  from  the  brain  and  spinal  marrow; 
if  there  are  exceptions,  you  will  find  that  even  there  the 
brain  sends  a  part  of  the  nerves. 

Q.  Are  the  muscles  abundantly  supplied  with  nerves? 

•&.  As  much  so  as  any  other  parts.  The  great  nervous 
trunks  run  in  the  direction  of  the  flexors. 

Q.   Are  the  flexor  or  extensor  muscles  the  strongest? 

«#.  Evidently  the  flexors;  in  hysteria,  in  infantile,  and 
all  other  involuntary  spasmodic  motions,  the  flexors  pre- 
dominate. So  they  do  in  old  people;  under  all  circum- 
stances the  motions  of  the  flexors  are  most  powerful. 


MUSCULAR    SYSTEM.  219 


Properties  of  the  Muscular  System  of  Jlnimal  Life. 

Q.  For  what  are  these  properties  remarkable? 

*/l.  The  muscles  have  slight  physical  and  conspicuous 
vital  properties.  You  have  heard  that  the  muscles  are 
slightly  elastic  and  soft. 

1.   Properties  of  Texture. 

Q.  What  property  of  texture  is  most  remarkable? 

t/#.  Extensibility;  and  this  is  in  the  flexor  or  extensor, 
as  the  one  or  the  other  may  be  passive.  Extensibility  is 
confined  to  the  muscular  fibre,  not  extending  to  the  ten- 
dons. 

Q.  What  morbid  phenomena  remarkably  illustrate  this 
property  in  the  muscles? 

«/?.  The  distention  of  the  muscles  with  tumours,  and 
that  in  pregnancy.  The  aponeuroses  have  some  influence 
in  preventing  their  distention  in  the  extremities. 

Q.  On  what  is  contractility  of  texture,  so  conspicuous 
in  muscles,  dependant? 

«/?.  Not  on  the  action  of  the  nerves,  not  entirely  on  life; 
it  is  on  the  structure  of  the  muscles  that  it  essentially  de- 
pends/ 

Q.  How  do  you  distinguish  contractility  of  texture  in 
the  muscles  from  the  vital  forces? 

*ft.  Between  the  extreme  points  of  extension  and  flexion 
of  the  moveable  parts  of  the  body  there  is  a  resting  point, 
or  a  middle  one.  To  remove  a  limb  from  this  point  of 
rest,  animal  contractility  or  a  vital  force  must  act  on  the 


220  MUSCULAR    SYSTEM. 

muscles.  Now,  as  long  as  this  vital  voluntary  power  is 
in  action,  the  textural  contractility  of  the  muscle  is  over- 
come. But  as  soon  as  this  vital  force  ceases  to  act,  the 
contractility  of  texture  restores  the  limb  to  the  medium  or 
resting  point.  When  the  will  acts  on  the  muscles,  vital 
forces  are  in  play;  when  it  ceases,  contractility  of  texture 
restores  the  limb  to  rest. 

Q.  What  is  the  cause  of  the  extended  limbs  in  typhus 
fever  in  its  last  stages? 

A.  It  does  not  proceed  from  increased  action  of  the  ex- 
tensors, but  from  a  loss  of  textural  contractility  in  the 
flexors. 

Q.  Can  you  give  instances  of  this  contractility  of  tex- 
ture in  action  ? 

*/#.  When  a  muscle  is  cut  through,  the  fibres  retract 
considerably;  when  a  woman  is  delivered,  the  abdominal 
muscles  return  to  a  natural  state  by  means  of  this  contrac- 
tility of  texture.  Repeated  distention  diminishes  this 
textural  property. 

Q.  How  does  long-continued  ascites,  affect  respiration 
even  after  the  water  has  been  removed? 

*ft.  Long-continued  pressure  of  the  water  on  the  dia- 
phragm diminishes  its  contractile  power,  and  dyspnoea 
continues;  so  it  is  after  repeated  pregnancy. 

Q.  To  what  is  this  contractility  of  texture  relative? 

«#.  It  is  in  proportion  to  the  length  of  the  fibres  of  the 
muscle ;  it  is  greatest  in  the  longest  muscles,  and  for  this 
reason  in  amputation  the  superficial  muscles  contract  the 
most.  In  sleep  the  legs  are  most  contracted. 

Q.  There  is  another  obvious  difference  between  this 
contractility  of  texture  and  the  vital  properties,  what  is  it? 


MUSCULAR    SYSTEM.  221 

*fl.  The  contractility  depends  on  the  development  of 
muscular  texture;  the  vital  forces  depend  on  the  varying 
impulses  of  cerebral  nervous  energy. 

Q.  What  destroys  contractility  of  texture  in  the  muscles? 

*#.  Putrefaction;  death  diminishes,  but  does  not  imme- 
diately destroy  it. 

Q.  What  distinguishes  this  contractility  from  the  horny 
hardening? 

J2.  In  the  same  organ  the  last  is  great,  the  first  slight, 
as  in  the  fibrous  organs.  Contractility  acquires  force 
from  life,  the  other  does  not.  Contractility  is  lost  in  the 
dried  organs,  the  other  is  not.  Contractility  is  slowly 
manifested,  the  other  rapidly.  The  absence  of  extension 
excites  contractility,  but  foreign  bodies  are  necessary  to 
produce  the  hardening. 

2.  Vital  Proper  ties  of  the  Muscular  System  of  Animal 

Life. 

Q.  Is  animal  sensibility  well  marked  in  healthy  muscle  ? 

«/?.  It  is  the  most  obscure  of  all  the  vital  properties; 
pain  in  cutting  a  muscle  is  not  severe;  irritants  do  not 
much  excite  them;  in  short,  the  peculiar  texture  of  the 
muscle  has  but  little  animal  sensibility. 

Q.  But  there  are  circumstances  in  which  this  property 
is  manifestly  conspicuous,  what  are  they? 

«/?.  In  the  lassitude  from  fatigue,  and  that  which  pre- 
cedes many  diseases,  it  is  seen.  In  the  first,  it  warns 
against  continued  exertion;  in  the*  second,  it  admonishes 
of  the  approach  of  disease.  In  the  inflammation  of  the 
peculiar  texture  of  muscles,  this  sensibility  is  most  acutely 
increased^  and  this  differs  from  lassitude. 


222  MUSCULAR    SYSTEM. 

Q.  What  vital  property  is  exclusively  seated  in  the 
muscular  system  of  animal  life? 

JL.  Animal  contractility,  on  which  depend  locomotion 
and  the  voice. 
'    Q.  In  what  does  this  animal  contractility  consist? 

•ft..  In  the  faculty  of  moving  under  cerebral  influence, 
whether  this  influence  is  produced  by  the  will,  or  any 
other  cause. 

Q.  In  what  general  character  do  the  vital  properties  of 
animal  life  differ  from  those  of  organic  life? 

•ft.  In  this;  that  the  exercise  of  the  properties  of  or- 
ganic life  is  concentrated  in  the  organs,  while  the  exer- 
cise of  those  of  animal  life  depend  on  the  organ,  the  brain, 
and  the  nerves. 

Q.  How  do  you  prove  the  brain  thus  essentially  con- 
nected with  the  muscular  system? 

•ft..  Causes  which  increase  the  energy  of  the  brain  have 
that  effect  on  the  muscles,  and  those  which  diminish  that 
energy,  debilitate  the  muscles. 

Q.  In  what  forms  are  sudden  and  powerful  impres- 
sions on  the  brain  manifested  in  the  muscular  system  of 
animal  life? 

•ft.  As  in  convulsions  and  palsy.  Indeed  this  muscular 
system  indicates  the  condition  of  the  brain.  The  muscles 
are  to  the  brain  what  the  arteries  are  to  the  heart. 

Q.  What  three  great  functions  have  their  seatinthe  brain? 

•ft..  Perception,  voluntary  motion,  and  intellect.  These 
may  be  separately  or  entirely  destroyed  or  affected. 

Q.  There  are  two  circumstances  whicli  influence  the 
cerebral  power  over  the  muscles,  what  are  they  ? 

•ft..  The  disposition  of  the  nerves  to  convey  this  power, 
and  that  of  the  muscles  to  receive  it. 


MUSCULAR    SYSTEM. 

Q.  Do  the  nerves  proceed  directly  from  the  brain  to 
the  muscles  of  animal  life  ? 

«/?.  Some  do,  but  the  greater  number  go  from  the  me- 
dulla spinalis. 

Q.  What  evidence  is  there  that  the  nerves  of  motion 
proceed  from  the  medulla  spinalis? 

./?.  If  the  medulla  spinalis  is  irritated,  convulsions  arise; 
and  as  this  irritation  is  higher  or  lower  on  the  medulla, 
are  the  superior  or  inferior  parts  irritated. 

Q.  Why  are  injuries  of  this  medulla,  at  its  upper  part, 
so  dangerous? 

.#.  Because  the  functions  of  the  diaphragm  and  inter- 
costal muscles  are  destroyed. 

Q.  What  nerves  go  directly  from  the  brain  to  the  mus- 
cles of  animal  life? 

Jl.  Those  to  supply  the  tongue,  face,  and  eyes,  and 
some  others. 

Q.  Are  all  the  nerves  of  animal  life  equally  disposed  to 
convey  irritation  from  the  brain? 

«/?.  No ;  those  of  respiration  are  least  so,  and  the  wis- 
dom of  this  is  evident.  The  muscles  of  the  extremities, 
face,  larynx,  pelvis,  abdomen,  intercostals,  and  diaphragm, 
are,  in  the  order  mentioned,  disposed  to  take  on  irritation 
from  the  brain. 

Q.  In  what  direction  is  nervous  influence  propagated? 

«/?.  From  the  superior  to  the  inferior  part  of  the  nerve 
only. 

Q.  What  circumstances  affecting  the  muscles,  alter  the 
animal  contractility  of  that  texture? 

*ft.  Inflammation,  contusion,  infiltration  of  serum;  in- 
terruption to  the  flow  of  blood,  for  the  arterial  motion, 
and  that  conveying  red  blood,  is  necessary  to  muscular 


224 


MUSCULAR-  SYSTEM. 


animal  contractility;  opium  thrown  into  contact  with  the 
muscular  texture;  all  these  alter  the  contractility  of  the 
muscles. 

Q.  Repeat  the  actions  necessary  to  excite  animal  con- 
tractility in  the  muscular  tissue? 

*#.  The  action  of  the  brain  which  originates,  that  of 
the  nerves  which  propagates,  and  that  of  the  muscles 
which  receive  the  principle  of  motion. 

Q.  What  causes  acting  on  the  brain  produce  animal 
contractility? 

*#.  The  exercise  of  the  will ;  and  there  are  involuntary 
ones  which  excite  this  property  without  the  concurrence 
of,  or  even  in  opposition  to  the  will.  These  involuntary 
causes  are  directly  applied  to  the  brain,  or  influence  that 
organ  by  sympathy. 

Q.  Are  these  sympathetic  impressions  always  attended 
with  increased  determination  of  blood  ? 

*#.  They  are  not;  it  is  irritation  simply;  and  this  irrita- 
tion excites  the  brain  to  a  degree  beyond  the  control  of 
volition,  and  convulsions  ensue. 

Q.  How  does  fear  act  on  the  muscles? 

•#.  Through  the  intervention  of  the  brain,  and  this  fear 
deprives  the  brain  of  its  power  to  originate  the  impulse  of 
the  contractility. 

Q.  How  do  you  account  for  muscular  action  in  the 
foetus,  where  the  will  evidently  cannot  act? 

*/2.  Sympathetic  impression,  derived  from  the  visceral 
organs,  acts  on  the  brain  producing  involuntary  muscular 
action  or  animal  contractility. 

Q.  Can  you  explain  the  muscular  motion  after  decapita- 
tion in  man  and  animals? 

•#.    The  brain  conveys  for  a  short  time  lo  the  face,  and 


MUSCULAR    SYSTEM.  225 

the  nerves  from  the  spine  convey  to  the  muscles  of  the 
body  and  limbs,  the  principle  of  animal  contractility. 
This  circumstance  clearly  shows  the  difference  between 
the  voluntary  and  involuntary  contractility.  So  that  after 
decapitation,  and  by  the  influence  of  galvanism,  the  prin- 
ciple of  animal  contractility  can  be  conveyed;  that  is,  after 
intellect  and  respiration,  and  the  heart's  action  have  irre- 
coverably ceased. 

Q.  Why  is  galvanism  more  powerful  after  death  than 
during  life  ? 

t/2.  Because  during  life  the  will  in  a  great  measure 
counteracts  the  irritation  of  the  galvanic  fluid. 

Q.  What  is  the  difference  between  animal  contractility 
and  irritability? 

*ft.  Animal  contractility  originates  in  the  brain  and 
nerves,  and  its  power  is  passively  received  by  the  mus- 
cles. Irritability  is  an  innate  principle  of  motion  in  a 
muscle;  it  exists  before  and  after  death. 

Q.  In  what  part  of  the  nervous  system  does  animal 
contractility  cease  first  and  last? 

«#.  It  is  first  lost  in  the  brain,  next  in  the  spinal  mar- 
row, last  in  the  nerves;  and  it  is  excited  by  metallic  irri- 
tation when  all  other  is  inefficient. 

Q.  By  what  means  can  you  distinguish  sensible  organic 
contractility  from  animal  contractility? 

jl.  Recollect  that  sensible  organic  contractility  is  or- 
ganic action  independent  of  the  brain,  the  animal  contrac- 
tility is  purely  dependent  on  the  brain.  If  you  cut  all  the 
nerves  which  convey  influence  to  the  muscle,  still  that 
muscle  on  irritating  it  will  contract;  now  this  is  the  sen- 
sible organic  contractility,  the  irritability  of  physiologists. 

29 


226  MUSCULAR    SYSTEM, 

This  irritability  actuates  a  muscle  from  contractions  down 
to  oscillations. 

Q.  What  tends  most  to  develope  the  sympathies  of 
this  system? 

.#.  The  great  development  of  animal  sensibility  in  any 
organ;  hence  it  is  that  pain  so  often  produces  involuntary 
animal  contractility  of  the  muscles,  or,  in  other  words, 
spasms. 

Q.  Is  this  sympathy  direct  between  the  organ  and  the 
muscles? 

•ft.  The  pain  acts  on  the  brain,  and  that  reacts  on  the 
muscles. 

Q.  Do  the  organic  sensibilities  and  contractilities  ra- 
diate sympathetic  reciprocity  through  the  brain  on  the 
muscles? 

*#.  No;  none  but  the  animal  sensibility  and  contrac- 
tility are  sympathetically  operative  through  the  brain;  the 
organic  vital  properties  operate  directly  from  organ  to 
organ. 

Q.  Is  there  an  anatomical  or  physiological  reason  for  this? 

«/?.  There  is;  for  the  brain  does  not  influence  organic 
vital  properties  through  the  nerves,  but  it  does  affect  the 
animal  properties  of  the  muscle. 

Q.  State  instances  of  animal  sensibility  in  the  muscular 
system  sympathetically  excited. 

«#.  Take  as  instances  of  this  the  pain,  languor,  and  las- 
situde of  fever. 

Q.  Do  convulsive  motions  indicate  disease  of  the  mus- 
cles? 

•#.  They  do  not;  they  indicate  cerebral  excitement  as 
the  varieties  of  the  pulse  indicate  affections  of  the  heart 


MUSCULAR    SYSTEM.  227 

Q.  Is  the  muscular  texture  very  liable  to  organic  dis- 
ease? 

•#.  No;  it  is  but  little  subject  to  this.  It  is  seldom  that 
the  tumours,  or  suppurations,  or  other  organic  affections, 
so  much  met  with  elsewhere,  are  found  in  the  muscular 
texture. 

Phenomena  of  the  Action  of  the.  Muscular  System  of 
Animal  Life. 

Q.  How  do  you  form  your  estimate  of  the  force  of 
muscular  contraction  ? 

A.  It  is  in  the  ratio  of  the  force  of  the  organization  of 
the  muscle,  and  that  of  the  cerebral  excitement 

Q.  What  are  the  three  sources  of  muscular  contraction  ? 

Ji.  Irritating  the  brain  in  experiments,  excitement  of 
the 'brain  in  the  natural  state,  and  sympathetic  influence. 

Q.  Does  the  rapidity  of  muscular  contraction  depend 
on  the  number  of  the  branches  of  the  nerves,  supplying 
the  muscles,  which  may  be  irritated? 

A.  The  contractions  are  as  rapid  if  you  irritate  one 
branch,  as  if  all  the  branches  are  irritated. 

Q.  Are  all  the  phenomena  of  muscular  contraction 
identical? 

A.  No;  cut  a  muscle  and  there  is  slow  and  insensible 
contractility  of  texture,  and  this  is  seen  in  muscles  where 
the  antagonizing  muscles  are  palsied.  Then  you  have  the 
rapid  contraction,  either  voluntary,  or  from  irritation  of 
the  nerve;  and  lastly,  you  have  that  oscillation  which  a 
chill  or  fear  produces. 

Q.   How  do  you  estimate  the  effect  which  a  muscle  in 


228  MUSCULAR    SYSTEM. 

the  straight  direction  produces  on  the  bones  into  which  it 
is  inserted? 

.#.  Take  the  direction  of  the  muscle  from  its  fixed  to 
its  moveable  point,  then  take  the  inverse  of  this  course, 
and  you  have  the  direction  of  the  motion. 

Q.  How  do  you  estimate  the  action  of  a  broad  muscle, 
which  is  united  in  a  single  tendon  or  point? 

./?.  Take  the  middle  line  of  direction  of  all  its  fibres. 

Q.  And  how,  when  the  fibres  attached  at  two  points 
form  several  fasciculi? 

>ft.  You  must  estimate  the  line  of  the  direction  of  each 
fasciculus,  and  then  you  can  decide  on  the  action  of  the 
muscle. 

Development  of  the   Muscular    System    of  Animal 

Life. 

Q.  What  is  the  colour  of  the  muscles  in  the  foetus? 

A.  The  tinge  is  that  of  venous  blood. 

Q.  What  excites  the  action  of  the  muscles  so  univer- 
sally as  they  are  seen  to  be  at  the  moment  of  birth? 

Ji.  The  contact  of  air,  which  excites  the  brain  to  per- 
ception of  impressions  new  to  it;  then  the  diaphragm  is 
excited  to  motion,  and  respiration  sends  red  blood  to  the 
brain;  this  blood  proving  an  additional  stimulus  to  cere- 
bral influence,  the  constant  and  active  muscular  motions 
of  infancy  are  produced. 

Q.  What  effect  has  disease  on  the  colour  of  the  mus- 
cles? 

.#.  Acute  diseases  have  little  effect;  in  chronic  cases  it 
often  becomes  pale;  in  dropsy  it  is  quite  pale. 


MUSCULAR    SYSTEM.  229 

Q.  How  does  age  affect  muscular  contractility  of  tex- 
ture? 

*#.  It  diminishes  it  remarkably. 

Q.   Is  the  muscular  fibre  globular,  hollow,  or  solid? 

«#.  Meckel  and  Home  consider  it  globular;  some  ana- 
tomists suppose  it  to  be  an  assemblage  of  vessels  of  a  par- 
ticular order;  others  say  it  is  solid  and  not  penetrated  by 
fluids. 

II.  OF  THE  MUSCULAR  SYSTEM  OP  ORGANIC  LIFE. 

Q.  Where  do  you  find  the  muscles  of  this  tissue? 

A.  In  the  thorax,  abdomen,  and  pelvis;  and  the  heart 
and  oesophagus,  the  stomach  and  intestines,  the  bladder 
and  uterus,  compose  it 

Forms  and  Organization  of  the  Muscular  System  of 
Organic  Life. 

Q.  What  are  the  forms  of  these  muscles? 

£.  They  form  hollow  muscular  cavities;  they  are  with- 
out tendons;  they  do  notarise  from  fibrous  membranes, 
nor  are  they  inserted  into  them ;  they  proceed  from,  and 
terminate  in  cellular  substance;  they  have  a  thin,  flat, 
membranous  form. 

Q.  What  is  the  direction  of  the  fibres? 

«/?.   It  is  not  single  as  in  the  muscles  of  animal  life,  but ' 
they  interlace  in  every  direction. 

Q.   What  advantage  is  this  interlacing  of  fibres  ? 

*1.  It  favours  the  diminution  of  the  diameters  of  the 
cavities  formed  by  these  muscles. 


230  MUSCULAR    SYSTEM. 

Q.  Does  cellular  substance  abound  in  these  muscles? 

j2.  Not  at  all;  very  little  is  found;  hence  it  is  that  drop- 
sies are  not  met  with  in  this  tissue. 

Q.  Are  blood-vessels  numerous  here  ? 

*#.  Yes;  blood  is  found  in  full  proportion  in  this  tissue. 

Q.  Whence  do  they  derive  their  nerves? 

«/?.  From  the  cerebral  and  ganglionic  system. 

Q.  In  what  organ  of  this  tissue  do  the  cerebral  nerves 
predominate? 

A.  In  the  stomach — the  par  vagum. 

Properties  of  the  Muscular  System  of  Organic  Life. 
1.  Properties  of  Texture. 

Q.  For  what  properties  are  the  organic  muscles  re- 
markable? 

«/?.  Especially  for  those  of  texture,  viz.  extensibility 
and  contractility. 

Q.  What  is  conspicuous  in  the  extensibility  of  these 
muscles? 

«/?.  The  rapidity  with  which  it  acts,  and  the  extent  of 
which  it  is  susceptible.  Observe  this  in  the  distention  of 
the  stomach  and  bladder. 

Q.  Why  are  the  muscles  of  animal  life  incapable  of  this 
rapid  and  great  extensibility? 

•fl.  Perhaps  because  they  are  intersected  by  numerous 
aponeuroses,  and  because  the  layers  of  their  fibres  are 
very  thick. 

Q.  Do  you  not  find  in  some  of  the  organic  muscles  an 
extensibility  of  a  peculiar  kind? 


MUSCULAR    SYSTEM.  231 

•tf.  We  do,  as  in  the  gravid  uterus  and  aneurismatic 
heart.  It  is  in  these  the  result  of  nutrition,  where  thick- 
ness of  parietes  is  added  to  extension. 

Q.  When  is  contractility  of  texture  most  obvious  in 
these  muscles? 

.#.  When  they  are  empty. 

Q.  What  property  or  power  empties  them  of  their  con- 
tents? 

t#.  Organic  contractility;  and  after  this  has  emptied 
the  hollow  muscles,  then  contractility  of  texture  closes 
them. 

Q.  What  regulates  the  degree  of  organic  contractility 
in  the  organic  muscles? 

.#.  It  is  in  proportion  to  the  fleshy  fibres;  hence  it  is 
in  such  activity  in  the  left  ventricle  of  the  heart,  in  the 
O3sophagus,  and  in  the  rectum. 

2.    Vital  Properties. 

Q.  Have  the  muscles  of  organic  life  much  animal  sen- 
sibility? 

t/2.  It  is  slight.  Harvey  found  the  heart  insensible,  the 
bladder  is  so  in  living  animals. 

Q.   Is  lassitude  felt  in  these  muscles? 

t#.  It  is  probable  that  hunger  may  be  partly  owing  to 
this.  The  sensation  in  the  bladder  when  permanently 
contracted  may  be  that  of  lassitude.  Perhaps  the  feeble 
pulse  after  long  fevers  may  result  from  a  lassitude  of  the 
fleshy  fibres  of  the  heart. 

Q.  What  have  you  to  say  of  the  animal  contractility  of 
these  muscles  of  organic  life? 

*#.  That  from  the  nature  of  the  property  it  is  foreign 


232  MUSCULAR    SYSTEM, 

to  them.  Cerebral  influence  and  irritation  are  necessary 
to  animal  contractility;  now,  as  the  will  has  no  influence 
over  these  muscles,  animal  contractility  cannot  be  expect- 
ed in  them.  Irritate  the  brain  with  the  scalpel,  with 
opium,  intoxication,  wounds  of  the  head,  mania,  and  while 
all  these  excite  the  animal  contractility  of  the  muscles  of 
animal  life,  there  being  no  such  property  in  the  muscles 
of  organic  life,  they  are  unmoved. 

Q.  But  do  you  not  find  the  brain  affected  by  disorder 
of  the  muscles  of  organic  life? 

«#.  No — in  most  vomitings,  the  irregular  motions  of  the 
intestines  which  take  place  in  diarrhoeas,  in  affections  of 
the  heart,  &c.  the  brain  is  not  diseased. 

Q.   In  syncope  is  the  brain  or  heart  first  affected? 

.#.   The  heart  is. 

Q.  The  brain  does  certainly  influence  the  stomach 
through  the  par  vagum  ? 

«#.  It  does;  but  cutting  the  par  vagum  does  not  affect 
the  stomach  as  the  section  of  a  nerve  going  to  a  muscle 
of  animal  life,  does  that  muscle.  While  irritating  the  par 
vagum  induces  the  stomach  to  contract,  yet  if  both  nerves 
of  that  pair  be  divided,  violent  vomiting  is  induced.  Now 
you  never  induce  contraction  in  a  muscle  of  animal  life  by 
cutting  off  its  supply  of  nervous  influence. 

Q.  Do  you  consider  Bichat's  arguments  and  facts  with 
regard  to  the  independence  of  the  organic  muscles  of  ce- 
rebral influence  as  conclusive? 

Jl.  No.  He  is  not  convinced  himself;  for  a  mixed  in- 
fluence is  admitted,  with  the  nature  of  which  he  is  unac- 
quainted; but  of  one  thing  he  is  assured,  that  the  cerebral 
influence  on  the  organic  muscles  is  entirely  different  from 
that  on  the  animal  muscles. 


MUSCULAR    SYSTEM.  233 

Q.  What  property  predominates  in  the  muscles  of  or- 
ganic life  ? 

*#.  Sensible  organic  contractility ;  but  organic  sensibi- 
lity is  also  very  conspicuous. 

Q.  How  are  stimuli  divided  with  reference  to  the  sen- 
sible organic  contractility  of  the  organic  muscles? 

«#.  Into  natural  and  artificial.  The  blood  is  the  natu- 
ral stimulus  to  the  heart,  the  urine  to  the  bladder,  food 
and  faeces  for  the  stomach  and  bowels.  Artificial  stimuli 
are  irritants  applied  after  death,  or  in  experiments. 

Q.  How  is  the  sensible  organic  contractility  of  this  tis-   ^ 
sue  affected  by  natural  stimuli? 

*ft.  It  is  altered  by  changes  in  the  quality  and  quantity 
of  fluids.  See  how  the  heart  is  hurried  when  chyle  enters 
it  after  digestion,  and  likewise  when  fluids  are  thrown  into 
the  veins. 

Q.  Is  this  sensible  organic  contractility  the  same  in  all 
the  organs? 

•ft  It  is  not.  It  is  peculiar,  inasmuch  as  each  organ  re- 
sponds to  its  peculiar  or  natural  stimuli — such  is  the  blood 
to  the  heart,  the  urine  to  the  bladder. 

Q.  What  is  the  state  of  this  property  at  different  ages? 

A.  It  is  most  active  in  youth;  it  becomes  less  so  in 

adult  and  advanced  life.  The  action  of  the  heart,  bladder, 

and  rectum  at  these  periods  of  life,  will  fully  illustrate 

this. 

Q.  Does  temperament  present  different  states  of  this 
property? 

*ft.  In  different  temperaments,  you  see  a  predominance 
of  this  property,  in  some  over  others.  Having  no  common 
centre  or  source  of  influence,  as  the  animal  muscles  have, 

30 


234  MUSCULAR    SYSTEM, 

the  contractility  of  the  organic  muscles  is  seldom  uni- 
form; one  organ  having  a  greater  quantum  than  others. 

Q.   Is  stimulus  applied  directly  to  the  organic  muscles? 

«#.  No;  a  membrane  interposes,  as  the  continuous  mem- 
brane from  the  blood-vessels  in  the  heart,  the  mucous 
membrane  for  the  stomach  and  intestines. 

Q.  Does  this  property  remain  after  death? 

*#.  It  is  obvious  after  sudden  general  death ;  you  do  not 
see  it  after  death  from  chronic  disease. 

Q.  In  which  of  the  organic  muscles  is  sympathy  most 
frequently  and  actively  developed? 

t/2.  In  the  heart,  next  in  the  stomach,  then  the  intes- 
tines, and  lastly  the  bladder.  In  this  order  the  sympa- 
thetic activity  is  conspicuous. 

Q.  What  are  the  two  modes  in  which  the  heart  sym- 
pathizes ? 

«/#.  By  having  its  action  enfeebled,  as  in  syncope,  and 
hurried,  as  in  fever.  This  increased  action  is  engendered 
in  three  ways;  by  foreign  matters  mixed  with  the  blood, 
by  preternatural  irritability,  and  by  sympathy. 

Q.  What  is  the  sensible  organic  contractility  of  the 
stomach? 

«#.  Vomiting. 

Q.  Is  bile  found  in  the  stomach  in  health? 

.#.  Bichat  says  he  has  always  found  it  in  animals.  Vo- 
miting is  not  occasioned  by  the  bile,  but  by  a  sympathetic 
action  of  the  fibres  of  the  stomach,  to  which  is  doubtless 
superadded  in  some  cases  a  sympathetic  affection  of  the 
mucous  lining  of  the  stomach.  It  is  these  which  occasion 
vomiting,  not  the4bile  in  the  stomach. 

Q.  What  property  in  a  tissue  is  affected  by  disease? 


MUSCULAR    SYSTEM.  235 

%/?.   That  which  predominates  in  a  tissue. 

Q.   Will  you  illustrate  tins  observation? 

.#.  In  those  textures,  the  mucous,  serous,  and  cutane- 
ous, for  instance,  where  insensible  organic  contractility  is 
predominant,  acute  phlegmasiae  are  most  common,  because 
this  property  presides  over  these  acute  inflammations.  In 
the  organic  muscles,  insensible  organic  contractility  is  fee- 
ble, the  diseases  therefore  of  these  muscles  are  those  of 
the  predominant  property,  which  is  sensible  organic  con-, 
tractility.  Hence  aqute  inflammation  comparatively 
rarely  attacks  the  muscular  substance  of  the  heart  or  sto- 
mach. Again,  animal  contractility  being  predominant  in 
the  muscular  system  of  animal  life,  you  find  that  property 
deranged  in  its  diseases, 

Phenomena  of  the  action  of  the  Muscular  System  of 
Organic  Life. 

Q.  What  is  to  be  observed  of  the  force  of  the  contrac- 
tions of  this  texture? 

Jl.  That  its  action  is  more  uniform  than  those  of  the 
muscles  of  animal  life;  this  action  never  being  either  con- 
vulsed or  palsied,  as  that  of  the  animal  muscles  is. 

Q.  What  controls  the  force  of  the  contractions  of  the 
organic  muscles? 

£.  Power  adapted  to  function,  and  the  circumstance 
of  there  being  solid  or  fluid  contents  to  evacuate. 

Q.  In  the  animal  muscular  system  antagonizing  mus- 
cles act  in  inducing  relaxation  after  contraction,  as  the 
triceps  and  biceps;  now  as  there  are  no  antagonizing  or- 
ganic muscles,  how  is  their  relaxation  effected? 

•$.  Dilatation    is,   from  observation,  proved   to   be  as 


236  MUSCULAR    SYSTEM. 

much  an  active  effort  as  contraction,  in  the  organic  mus- 
cles; the  powers  of  both  are  s6  intermingled  as  not  to  be 
separable. 

Development  of  the  Muscular  System  of  Organic  Life. 

Q.  Is  it  the  action  of  the  brain  at  birth  which  sets  the 
'  organic  muscles  into  activity  ? 

e#.  The  principle  has  been  adopted  that  these  muscles 
are  independent  of  the  brain. 

Q.  What  causes  then  excite  them? 

<&.  One  cause  is  sympathy  with  the  external  skin,  which 
is  irritated  by  the  contact  of  air  at  birth;  another  is,  the 
excitement  on  the  beginning  of  the  mucous  surfaces,  and 
on  the  whole  lungs,  in  breathing.  Other  causes  are  fluids 
taken  into  the  stomach,  the  red. blood  penetrating  the  or- 
ganic muscles,  instead  of  fetal  black  blood;  and  lastly,  the 
meconium  stimulates  the  bowels. 

Q.  Does  growth  in  the  external  parts,  and  in  the  or- 
ganic muscles,  cease  at  the  same  time? 

•ft.  No;  each  part  has  its  period  of  full  growth;  the  or- 
ganic muscles  are  longer  in  attaining  this  than  others. 
The  organic  muscles  are  not  subject  to  the  irregularities 
of  growth,  that  so  remarkably  characterize  the  animal 
muscles. 

Q.  Why  do  nutrition  and  growth  vary  in  different  tex- 
tures? 

•#.  Because  they  depend  on  the  vital  forces,  which  vary 
in  every  tissue. 

Q.  Which  of  the  muscular  systems  is  soonest  exhausted? 

»#.  Both  in  exercise  and  life  the  animal  muscular  sys- 
tem is  soonest  exhausted. 


MUSCULAR    SYSTEM.  237 

Q.  Does  Beclard  suppose  that  the  brain  influences  the 
organic  muscles? 

*ft.  He  thinks  it  does  not  ordinarily,  but  may  contin- 
gently. 

Q.  What'distinguished  French  pathologist  was  an  in- 
stance of  the  controlling  power  of  the  will  over  one  of  the 
organic  muscles? 

•ft.  Bayle  could  at  will  suspend  the  action  of  the  heart. 

/  * 


PATHOLOGY  OF  THE  MUSCULAR  TISSUE. 

Q.  What  are  the  diseases  of  the  muscular  system  of 
animal  life? 

«/?.  Rheumatism,  lassitude,  atrophy,  and  hypertrophy. 

Q.   Is  inflammation  frequent  in  the  muscular  tissue? 

Jl.  It  is  not;  it  arises  in  the  cellular  tissue  of  the  mus- 
cles. 

Q.  What  is  to  be  observed  of  the  diseases  of  the  mus- 
cles of  organic  and  of  animal  life? 

A.  That  those  of  the  organic  muscles  are  various,  from 
the  variety  of  organs,  and  those  of  the  animal  muscles  are 
few,  from  the  uniformity  of  the  texture. 

Q.  What  are  the  diseases  of  the  heart? 

«#.  Inflammation,  acute  and  chronic;  syncope;  palpita- 
tion; aneurism;  rupture. 

Q.  What  is  the  pathology  of  syncope? 

«/?.  It  is  a  loss  of  contractility  in  the  heart. 

Q.  What  do  you  observe  of  the  intermittent  pulse  in 
fever  and  disease  of  the  heart? 


238  MUSCULAR    SYSTEM. 

Jl.  That  pulse  is  more  dangerous  in  fever  than  in  dis- 
ease of  the  heart. 

Q.  What  are  the  causes  of  palpitation  ? 

A.  It  arises  from  fulness  of  blood;  from  excitation  of 
the  heart  by  mental  emotion;  from  obstruction"  to  the  pas- 
sage of  blood  through  the  lungs;  it  proceeds  also  from  me- 
chanically distended  stomach. 

Q.  How  do  you  distinguish  suffocation  caused  by  the 
heart,  and  that  produced  by  the  lungs? 

Ji.  In  that  caused  by  the  heart,  the  patient  cannot  bear 
the  recumbent  posture,  there  is  violent  dry  cough.  When 
the  patient  lies  down,  the  heart  presses  against  the  lungs, 
and  occasions  the  suffocation. 

Q.  What  is' the  seat  of  polypus  of  the  uterus? 

Jl.  It  is  either  on  the  mucous  surface,  or  arises  from 
the  muscular  tissue  of  the  uterus. 

Q.  What  muscles  are  least  affected  with  rheumatism? 

<&.  The  abdominal. 

Q.  What  symptom  attends  diaphragmatic  rheumatism? 

Jl.  Hiccup. 

Q.  What  occasions  atrophy  of  the  muscles  of  animal 
life? 

t#.  Paralysis,  tyi,ng  up  the  artery  which  supplies  the 
muscle. 


239      ) 


MUCOUS  SYSTEM. 

Q.  Why  is  this  called  the  mucous  system? 
•fl.  From  the  fluid  which  is  found  on  the  surface  of  the 
tissue  which  composes  it.  , 

Of  the  Divisions  and  Form  of  the  Mucous  System. 

Q.   In  what  form  does  this  texture  appear? 

«/2.   Always  in  a  membranous  form. 

Q.   Where  are  these  membranes  found? 

•ft.  They  line  all  the  interior  surfaces  which  communi- 
cate externally. 

Q.  How  are  these  membranes  generally  divided? 

«/?.   Into  the  gastro-pulmonary  and  genito-urinary. 

Q.  Is  there  no  mucous  tissue  which  is  not  embraced  in 
these  two  divisions? 

«/?.  There  is  a  small  mucous  surface  in  the  tubes  of  the 
nipple. 

Q.  Give  a  general  view  of  the  gastro-pulmonary  mucous 
membrane. 

«/#.  It  lines  the  mouth,  nose,  anterior  face~of  the  eyes, 
the  ducts  of  the  glands  of  the  mouth  and  throat;  it  lines 
the  Eustachian  tube,  the  trachea,  lungs,  the  oesophagus, 
stomach,  the  biliary,  pancreatic  and  cystic  ducts,  the  in- 
testines, and  finally  unites  with  the  skin  at  the  rectum. 

Q.  Give  a  similar  view  of  the  genito-urinary  mucous 
membrane. 

A.  This  is  spread  in  men  on  the  urinary  canals  up  to 


240  MUCOUS    SYSTEM. 

the  kidneys,  along  the  seminal  ducts  and  tubes;  and  in 
women  on  the  urinary  canals,  on  the  vagina,  uterus,  and 
fallopian  tubes,  and  by  the  opening  of  these  tubes  it  com- 
municates with  the  peritoneum. 

Q.  Is  it  common  for  the  mucous  and  serous  membranes 
.to  communicate? 

«/#.  This  just  stated  is  the  only  instance. 

Q.  State  some  interesting  pathological  considerations 
which  refer  to  these  two  mucous  surfaces. 

e/?.  The  diseases  of  these  two  great  divisions  of  the  mu- 
cous membranes  are  distinct,  and  sympathies  radiate  be- 
tween them  comparatively  rarely.  But  there  are  sympa- 
thies which  play  between  them  deserving  recollection, 
such  as  that  between  the  utero-mucous  and  pulmonary 
mucous  surfaces,  constituting  vicarious  haemorrhage  from 
the  lungs  when  menstruation  is  interrupted.  The  trans- 
lation of  gonorrhoea  to  the  mucous  membrane  of  the  eye 
is  another  instance. 

Q.  Will  you  state  some  curious  sympathetic  irritations 
which  arise  in  the  courses  of  these  two  divisions  of  the 
mucous  system? 

«#.  The  irritation  at  the  end  of  the  penis  occasioned  by 
a  stone  in  the  bladder  is  one,  and  the  itching  of  the  nose 
occasioned  by  worms  on  the  intestinal  surface  is  another. 

Q.  How  many  surfaces  are  presented  by  each  mucous 
membrane  ? 

Jl.  Two;  an  adherent  one  to  the  neighbouring  organs, 
and  a  free  villous  one. 

Q.  What  are  the  uses  of  the  adherent  mucous  surface? 

.#.  By  its  adhesion  to  the  muscles  of  organic  and  animal 
life,  it  has  a  constant  agitation,  favourable  to  the  secretion 
of  mucus;  it  gives  form  to  the  organ  it  lines ;  it  gives  force 


MUCOUS    SYSTEM.  241 

to  the  mucous  surface,  and  it  resists  the  contents  of  the 
mucous  cavities. 

Q.  Will  you  name  an  important  aspect  in  which  the 
mucous  system  deserves  here  to  be  considered:' 

»tf.  It  is  the  constant  exposure  of  the  mucous  surfaces 
to  foreign  bodies  and  matters;  the  tissue  serves  to  defend 
organs  from  the  contact  of  these  bodies;  in  this  office  it  is 
to  the  internal  organs  what  the  skin  is  to  the  external. 

Organization  of  the  Mucous  System. 

Q.  What  is  the  mucous  chorion  ? 

Jl.  The  layer  and  papillae  of  the  free  surface. 

Q.  What  is  the  texture  lining  the  ear? 

•ft.  Its  continuity  with  the  pituitary  membrane,  its  mu- 
cous discharge,  its  diseases,  its  want  of  fibres,  prove  it  to 
be  mucous  tissue. 

Q.  Where  is  the  mucous  chorion  thickest? 

•/?.  In  the  gums  and  palate;  it  is  finest  in  the  sinuses 
of  the  face  and  internal  ear.  Diseases  thicken  it  very 
much. 

Q.  What  is  its  texture? 

•ft.  It  is  soft  and  thick,  like  velvet,  in  the  stomach  and 
intestines;  as  it  approaches  the  external  openings,  it  be- 
comes denser.  The  extreme  softness  of  the  texture  in  the 
internal  organs  will  not  allow  of  the  variolous  pustule ; 
these  pustules  appear  on  the  mucous  surface,  where  its 
density  will  support  their  structure. 

Q.   Where  is  the  mucous  chorion  of  the  deepest  colour? 

Jl.  In  the  stomach,  where  blood  gives  it  this  colour;  it 
is  paler  in  the  bladder  and  rectum. 

Q.  What  effect  have  the  mucous  surfaces  on  milk? 
31 


242  MUCOUS   SYSTEM. 

*fl.  The  dried  membrane  coagulates  it. 

Q.  In  what  is  the  peculiar  sensibility  of  the  mucous 
texture  seated  ? 

«#.  In  the  papillae  of  the  mucous  chorion. 

Q.  In  what  part  of  the  mucous  tissue  does  functional 
power,  such  for  example  as  the  secretion  of  gastric  juice, 
reside  ? 

t#.  In  the  vascular  net-work  at  the  base  of  the  villi, 
not  in  the  villi  themselves,  as  has  been  supposed.  The 
villi  are  adapted  to  sensibility,  not  to  secretion. 

Q.  What  experiment  decided  the  function  of  the  villi  ? 

»#.  Irritate  the  villi  after  removing  the  epidermis,  and 
great  pain  is  felt;  introduce  an  instrument  so  as  to  irritate 
the  internal  surface  of  the  chorion,  and  no  pain  is  felt. 
The  base  of  the  papillae  is  nervous,  and  the  papillae  receive 
the  impression  of  foreign  bodies. 

Q.  Are  these  papillae  susceptible  of  erection? 

«#.  Certain  portions,  as  the  tongue  and  nose,  are  sup- 
posed to  have  an  erectile  capacity,  somewhat  resembling 
the  corpus  cavernosum  penis. 

Q.  Whence  proceeds  the  mucus  which  lines  this  texture? 

*ft.  From  the  glands  called  mucous.  They  are  found  un- 
der the  chorion;  they  are  largest  in  the  velum  palati  and 
mouth,  and  they  are  rounded  in  form. 

Q.  What  difference  is  observable  in  the  serous  and 
mucous  fluids? 

*#.  The  mucus  is  secreted;  the  serum  exhaled. 

Q.  If  the  glands  are  seated  beneath  the  chorion,  how 
are  they  excited  to  secretion  by  foreign  bodies? 

*#.  These  bodies  irritate  the  extremities  of  the  ducts 
which  convey  the  mucus,  and  thus  the  glands  are  irri- 
tated. 


MUCOUS    SYSTEM.  243 

Q.  What  becomes  of  the  mucus  which  is  poured  out  so 
freely  ? 

«#.  It  is  evacuated  from  the  various  outlets;  it  is  en- 
tirely excrementitious. 

Q.  What  pathological  consideration  is  inferred  from 
the  vast  quantity  of  mucus  secreted? 

.#.  Amongst  others  this,  that  the  secretion,  when  sup- 
pressed, must  give  rise  to  disease. 

Q.  What  general  difference  is  observed  in  the  destina- 
tion of  secreted  and  exhaled  fluids? 

./?.  Secretions  are  excrementitious;  exhaled  fluids  are 
recrementitious.  One  of  many  proofs  of  the  excrementi- 
tious tendency  of  mucus,  is  the  uneasiness  an  accumula- 
tion of  it  occasions,  and  the  efforts  by  coughing  to  re- 
move it. 

Q.  Is  this  texture  full  of  blood-vessels? 

*#.  It  receives  a  great  many  blood-vessels. 

Q.  Where  is  it  most  red? 

t/2.  In  the  stomach;  and  the  colour  depends  on  a  net- 
work of  blood-vessels,  which  penetrate  the  mucous  cho- 
rion  spread  on  its  surface,  and  embrace  the  papillae. 

Q.  What  results  from  the  superficial  situation  of  the 
blood-vessels? 

JL.  The  frequency  of  haemorrhage  from  the  mucous 
tissue. 

Q.  What  arises  from  long  exposure  of  portions  of  the 
mucous  surface  to  the  air? 

A.  It  is  brought  to  resemble  the  skin;  in  certain  cases 
of  vaginal  prolapsus,  hermaphrodism  has  been  affirmed. 

Q.  Is  there  any  reason  to  believe  that  the  redness  of 
the  mucous  membranes  is  owing  to  the  blood  being  oxy- 
genated through  their  surfaces,  as  it  is  in  the  lungs? 


244 


MUCOUS    SYSTEM, 


•ft.  Experiments  contradict  the  supposition, 

Q.  Does  the  redness  of  this  tissue  depend  on  the  blood 
circulating  in  the  arteries? 

<fl.  It  does  not;  it  arises  from  the  colouring  matter  of 
the  blood  combined  with  the  texture. 

Q.  Why  is  it  of  so  much  importance  to  know  the  nor- 
mal colour  of  the  mucous  membranes? 

*#.  In  order  to  decide  on  their  pathological  state. 

Q;  How  do  the  exhalents  on  this  texture  favour  haemor- 
rhage? 

JL.  By  the  course  being  so  very  short  from  the  artery, 
through  the  exhalent,  to  the  mucous  surface.  From  this 
it  is  inferred  that  haemorrhage  is  from  exhalation  and  not 
from  rupture;  and  haemorrhage  is  incomparably  more  fre- 
quent from  this,  than  from  other  textures. 

Q.  What  forms  the  pulmonary  perspiration? 

•#.  A  considerable  portion  of  it  is  a  solution  of  the  mu- 
cous fluid  which  lubricates  the  bronchiae. 

Q.  How  is  absorption  evidenced  in  this  texture? 

«#.  By  the  absorption  of  chyle  and  fluids  swallowed, 
on  the  intestinal  surfaces;  by  the  absorption  of  morbid 
matters;  by  the  absorption  of  the  urine  in  the  bladder;  by 
the  absorption  of  turpentine  vapours  on  the  bronchial  sur- 
face. 

Q.  How  do  the  mucous  and  serous  absorptions  differ? 

«#.  Exhalations  and  absorption  are  relative  to  each 
other,  and  regular  on  the  serous  surfaces;  but  not  so  on 
the  mucous. 

Q.  What  nerves  supply  the  origins  of  the  mucous  sur- 
faces ? 

»#.  Where  these  surfaces  are  in  relation  to  external  bo- 


MUCOUS    SYSTEM.  245 

dies  like  the  skin,  the  cerebral  nerves  go  to  them;  other- 
wise the  mucous  nerves  are  ganglionic. 

Q.   Recapitulate  the  organization  of  the  mucous  tissue? 

A.  It  consists  of  an  adhering  sub-mucous  cellular  coat, 
of  a  free  surface,  a  mucous  chorion,  a  vascular  net-work 
composed  of  blood-vessels,  nerves,  exhalents,  mucous 
glands,  and  papillae. 

Properties  of  the  Mucous  System. 

1.   Properties  of  Texture. 

Q.  What  properties  of  texture  are  manifest  in  the  mu- 
cous tissue? 

«#.  Extensibility  and  contractility  are  evident,  but  these 
are  unequally  active  in  the  tissue.  The  stomach  and 
bowels  possess  them  to  a  great  degree;  the  ureter  is  more 
distensible  than  the  urethra. 

Q.  When  fluids  cease  to  pass  through  the  mucous  ca- 
nals, what  takes  place? 

«/?.  They  contract,  but  never  adhere.  When  blood 
ceases  to  pass  through  an  artery,  it  closes  and  becomes  li- 
gamentous;  not  so  with  the  mucous  canals.  What  bad 
consequences  must  result  if  there  existed  in  the  bowels  or 
urethra  a  disposition  to  close. 

2.    Vital  Properties. 

Q.  What  are  the  active  vital  properties  of  the  mucous 
tissue? 

A.  Animal  sensibility  is  essential  and  conspicuous.  In 
the  perception  of  odours,  on  the  vaginal  and  urethral  sur- 


246  MUCOUS    SYSTEM. 

faces,  and  on  the  glans  penis,  it  is  much  more  acute  than 
on  the  skin. 

Q.  Why  is  animal  sensibility  so  manifest  on  this  tis- 
sue? 

*ft.  In  order  to  watch  the  impression  of  foreign  bodies, 
to  the  contact  with  which  it  is  constantly  liable. 

Q.  What  effect  has  habit  on  the  animal  sensibilities  of 
the  mucous  tissues? 

t/?.  It  renders  sensations  which  are  at  first  painful, 
either  indifferent  or  pleasant,  and  vice  versa.  As  you  ad- 
vance in  life,  repeated  and  habitual  contact  diminishes  the 
sensibility  of  the  tissue. 

Q.  Why  is  it  that  the  gall-bladder  does  not  perceive 
bile? 

*#.  Because  habit  and  uniformity  of  perception  allow 
no  comparative  sensations. 

Q.  What  effect  has  disease  on  the  animal  sensibility  of 
this  texture  ? 

A.  It  raises  it  considerably,  but  never  to  such  exalta- 
tion as  is  felt  in  the  serous  and  cellular  tissues. 

Q.  Is  there  much  animal  contractility  in  the  mucous 
tissue? 

•#.  There  is  none. 

Q.  What  organs  feel  most  acutely  in  disease? 

t/?.   Those  which  feel  least  in  a  natural  state. 

Q.  What  properties  of  organic  life  are  conspicuous  in 
the  mucous  tissue? 

Ji.  Both  organic  sensibility  and  insensible  organic  con- 
tractility; and  these  are  kept  in  activity  by  the  nutrition, 
exhalation,  absorption,  and  secretion,  which  go  on  in 
these  tissues. 


MUCOUS    SYSTEM. 

Q.  What  is  remarkable  of  the  properties  alluded  to  in 
the  last  answer? 

*/?.  That  they  are  liable  to  higher  degrees  and  greater 
varieties  of  exaltation  than  in  other  tissues.  From  this  fact 
results  the  consequence  that  these  tissues  are  subject  to  a 
variety  of  diseases. 

Q.  How  does  Bichat  divide  the  sympathies  of  this  tex- 
ture? 

t/tf.  Into  active  and  passive.  In  the  first  it  influences 
other  parts;  in  the  second  it  is  influenced  by  those  parts. 

Q.  Repeat  the  general  law  of  sympathies,  which  we 
have  more  than  once  alluded  to. 

«/?.  That  they  act  on  the  predominant  vital  properties 
of  a  part;  for  instance,  exciting  animal  sensibility  where 
that  predominates,  or  animal  contractility,  or  sensible  or- 
ganic contractility,  according  as  the  one  or  other  may  be 
the  principal  vital  property. 

Q.  It  is  important  to  recollect  the  active  sympathies  of 
the  mucous  surfaces,  will  you  give  illustrations  of  them? 

*/2.  Irritation  on  the  pituitary  membrane  excites  the 
animal  contractility  of  the  diaphragm  to  sneezing. 
•ftnimal  sensibility  is  excited  sympathetically  at  the  glans 
penis,  by  a  stone  irritating  the  mucous  membrane  of  the 
bladder;  the  same  vital  property  is  in  action  when  worms 
in  the  intestines  induces  itching  at  the  nose.  The  semen 
passing  the  urethra,  excites  the  sensible  organic  contrac- 
tility of  the  heart  to  increased  action;  the  same  vital  pro- 
perty in  the  stomach  is  exalted  in  the  vomiting  occasion- 
ed by  the  irritation  of  a  stone  on  the  lining  membrane  of 
the  pelvis  of  the  kidney.  You  see  a  sympathetic  excite- 
ment of  organic  sensibility  and  insensible  organic  con- 


2  ib  MUCOUS    SYSTEM. 

tractility^  when  a  sialogogue  acting  on  the  extremity  of 
the  salivary  duct,  induces  a  discharge  of  saliva  from  the 
glands;  another  instance  of  this  sympathy  is,  when  the 
mucous  membrane  on  the  tongue  is  furred  in  consequence 
of  disordered  stomach ;  and  lastly,  a  very  remarkable  sym- 
pathy of  these  properties  with  the  mucous  membranes  is, 
when  the  cutaneous  organ  sympathizes  with  them  during 
digestion.  To  the  sympathies  of  insensible  organic  con- 
tractility and  organic  sensibility,  are  to  be  ascribed  the 
haemorrhages  which  one  mucous  tissue  assumes  vicarious 
to  those  of  another  portion  of  this  texture. 

Q.   In  passive  sympathies  this  tissue  is  influenced  by 
diseases  of  other  textures,  give  examples  of  this. 

t#.  In  several  diseases  of  other  tissues  you  have  burning 
sensations  in  the  mucous  membranes  of  the  mouth,  bowels, 
and  stomach ;  in  some  cases  there  is  great  thirst.  Now, 
in  these  cases  the  animal  sensibility  of  the  mucous  tis- 
sue is  in  passive  sympathy.  Again,  the  influence  of  cold 
applied  to  the  skin,  on  haemorrhage  of  the  mucous  tissue, 
is  a  passive  sympathy  of  the  insensible  organic  contrac- 
tility; so  likewise  are  the  catarrhs  from  exposure  to  cold, 
and  the  effect  of  warm  bathing  in  catarrh ;  also  the  disor- 
der of  certain  portions  of  the  mucous  membrane  in  some 
diseases,  as  that  of  the  throat  in  eruptive  cases;  lastly,  the 
diarrhoea  in  chronic  diseases,  and  the  pectoral  haemor- 
rhages in  the  last  stages  of  organic  diseases;  these  are  all 
passive  sympathies  of  the  insensible  organic  contractility 
of  the  mucous  membranes. 

Q.  Why  are  there  not  sympathies  of  the  other  vital 
properties  in  the  mucous  texture? 

t#.  Because  these  properties  are  either  not  in  existence, 


MUCOUS    SYSTEM. 

or  are  not  the  predominating  ones  of  the  texture;  for  you 
know  sympathies  play  upon  the  predominant  vital  proper- 
ties of  a  tissue. 

Q.  State  the  most  important  characters  of  the  vital  pro- 
perties of  this  texture. 

Jl.  They  are  constantly  active;  each  portion  of  the  tis- 
sue has  its  peculiar  modification  of  vital  properties  in  con- 
sequence of  peculiar  organization;  and  from  these  varieties 
in  the  vital  forces  result  the  various  diseases  of  this  tissue. 

Q.  Can  you  explain  what  you  refer  to  the  peculiarity 
of  the  vital  forces? 

•ft.  One  stimulus  exalts  those  of  the  pituitary  mem- 
brane, another  those  of  the  urethra,  while  a  third  increases 
those  of  the  stomach.  The  vital  force  of  each  is  in  rela- 
tion to  its  peculiar  stimulus. 

Q.  Is  the  mucous  secretion  alike  in  all  parts  of  the 
tissue? 

&.  In  different  parts  of  the  texture  it  is  very  different 
both  in  health  and  disease. 

Q.  What  part  of  the  mucous  system  has  the  most  ex- 
tensive range  of  sympathies? 

A.  That  of  the  stomach ;  the  least  affection  of  which 
organ  induces  by  sympathy  the  greatest  uneasiness. 

Q.  But  is  it  the  mucous  membrane  of  the  stomach 
which  is  the  source  and  seat  of  the  active  and  passive 
sympathies? 

A.  The  other  tissues  of  the  stomach,  such  as  the  serous 
and  muscular,  have  common  organization,  while  that  of 
the  mucous  is  peculiar.  Hence  it  is  probably  the  seat  of 
normal  and  abnormal  sympathy, 

32 


250  MUCOUS    SYSTEM 


Development  of  the  Mucous  System. 

Q.  Is  there  any  thing  remarkable  in  the  development 
of  the  mucous  surfaces  at  the  various  periods  of  life? 

*/2.  It  is  highly  important  that  the  physician  should  re- 
collect the  following  circumstances: — the  sudden  impulse 
given  to  the  vital  forces  of  this,  tissue  at  birth,  when  the 
meconium  and  urine  stimulate  to  their  discharge;  that  the 
soft  delicacy  of  the  mucous  tissues  of  the  stomach,  lungs, 
and  bowels,  may  render  children  so  liable  to  cough,  vo- 
miting, and  diarrhoea;  that  haemorrhages  from  this  texture 
in  youth  are  very  active;  that  the  colour  of  the  mucous 
membrane  is  bright  red  till  the  thirtieth  year;  that  this 
colour  varies  greatly  in  redness,  and  that  at  particular 
periods  of  life  the  gastro-pulmonary  and  genito-urinary 
mucous  tissues  are  in  especial  susceptibility  to  disease. 

Q.  Why  are  contagious  diseases  less  liable  to  be  taken 
at  advanced  periods  of  life? 

«/#.  Because  the  mucous  membranes  are  less  irritable, 
and  not  so  susceptible  of  disease  as  in  youth. 

Q.  What  does  Beclard  consider  as  the  structure  of  the 
papillae  or  villi? 

«#.  That  they  are  a  net-work  of  vessels  of  the  form  of 
leaflets,  slightly  curved  round  each  other,  but  it  is  not 
clearly  shown  whether  they  have  orifices  or  not. 

Q.  What  is  meant,  according  to  Beclard,  by  the  mu- 
cous follicles? 

Jl.  They  are  what  have  been  improperly  termed  mu- 
cous glands.  Instead. of  being  glands,  they  are  inversions 
under  the  free  surface  of  the  membrane  in  which  they  are 
formed ;  they  are  folded,  form  a  cul-de-sac,  and  end  in  an 


MUCOUS    SYSTEM.  251 

opening  on  the  free  surface.  They  vary  much  in  size; 
they  are  simple  or  compound. 

Q.  What  do  you  understand  by  the  alveolar  structure 
of  the  mucous  tissues? 

t#.  They  are  small  superficial  cavities  found  in  the  gas- 
tric and  intestinal  mucous  surface  by  Mr.  Hewson,  and 
more  accurately  described  by  Mr.  Home.  They  are 
called  alveolar  from  their  resemblance  to  the  cells  of  bees. 

Q.   How  do  they  differ  from  follicles? 

»#.  In  this,  that  their  mouths  are  broader  than  their 
bottoms. 

Q.  State  an  important  fact  as  to  the  follicles  and 
alveoli. 

*ft.  It  has  been  ascertained  that  in  herbivorous  animals, 
the  follicles  are  more  complicated  in  structure,  and  secrete 
a  more  active  juice.  In  carnivorous  animals  they  are 
more  simple,  and  resemble  alveoli.  In  omnivorous  animals, 
in  man,  they  are  of  both  kinds  on  the  mucous  surface. 

Q.  How  does  follicular  secretion  differ  from  glandular, 
and  from  exhalation? 

A.  In  follicles,  the  secreted  fluid  is  brought  directly  by 
the  extremities  of  the  arteries;  the  secreted  fluid  remains 
in  the  follicular  cavity  to  be  elaborated  before  it  is  thrown 
out  on  the  organ. 

Q.  What  is  the  nature  of  the  membrane  lining  abscesses 
and  fistuke? 

./?.   They  are'evidently  mucous. 

Q.   Under  what  circumstances  do  mucous  canals  close? 

t#.  When  by  any  cause  an  inflammation  arises  which 
destroys  the  mucous  surfaces;  then  the  parts  in  contact 
cicatrize. 


MUCOUS    SYSTEM- 


PATHOLOGY  OP  THE  Mucous  TISSUE, 

Q'.  What  are  the  diseases  common  to  all  the  mucous 
tissues? 

*#.  Increased  action  to  inflammation;  mucous  discharge; 
haemorrhage;  aphthae;  and  fungous  excrescences. 

Q.  Are  all  the  increased  mucous  discharges  from  in- 
flammation ? 

«#.  They  are  not;  both  irritation  and  relaxation  will 
produce  them. 

Q.  What  are  the  inflammations  or  catarrhs  of  this  tissue 
most  usually  produced  by  ? 

*ft.  By  atmospheric  changes. 

Q.  How  do  these  changes  act? 

.#.  Directly  on  some  of  the  mucous  tissues,  and  by 
means  of  cutaneous  sympathy  on  others. 

Q.  What  is  the  character  of  the  pain  in  these  mem- 
branes? 

«#.   It  is  not  lancinating  or  severe,  as  in  other  tissues. 

Q.  What  effeqt  has  mucous  inflammation  on  the  neigh- 
bouring cellular  texture? 

J2.  That  texture  is  not  excited  to  inflammation  by  mu- 
cous disease,  as  in  the  diseases  of  other  tissues. 

Q.  What  is  the  colour  of  the  mucous  membranes  in  in- 
flammation ? 

A.  They  are  from  a  rose  colour  to  deep  brown;  this 
colour  is  sometimes  arborescent,  and  sometimes  in  dotted 
points,  when  the  villi  are  inflamed;  lastly,  the  colour  is 
in  red  spots. 

Q.   How  do  these  inflammations  terminate? 

«#.   Not  in  adhesion,   but   in    mucous   discharges,    or 


MUCOUS    SYSTEM.  253 

mu co-purulent 5  in  haemorrhage;  in  thickening  of  the  mu- 
cous membranes.  They  terminate  rarely  in  gangrene. 
This  does  take  place  in  angina. 

Q.  There  is  one  remarkable  termination  omitted. 

«/?.  It  is  the  formation  of  membranes — as  in  croup  and 
in  the  intestines. 

Q.  Is  the  morbid  mucus  alike  in  all  the  membranes  ? 

t/2.  It  is  not;  it  varies  in  them  very  much ;  and  even  in 
the  same  membrane  at  different  periods  the  mucus  is  of 
different  colour  and  nature,  becoming  pus. 

Q.  When  mucous  membranes  are,  from  any  unnatural 
cause,  disused,  what  takes  place? 

«/#.  They  contract  and  close. 

Q.  What  is  the  nature  of  the  membrane  lining  fistulse? 

i/?.  It  is  mucous. 

Q.  On  what  do  the  morbid  growths  and  enlargements 
on  the  mucous  membranes  depend? 

t/?.  On  morbid  action  and  development  of  the  mucous 
capillaries,  from  long-continued  irritation  and  chronic  in- 
flammation. 

Q.  What  are  the  causes  of  mucous  haemorrhage? 

t#.  They  are  from  exhalation  and  disorganization,  not 
from  rupture. 

Q.  Whence  may  exhalation  of  blood  in  mucous  mem- 
branes arise? 

«#.  From  an  exaltation  or  diminution  of  the  vital  forces 
of  the  membranes.  Hence  the  active  and  passive  haemor- 
rhages. 

Q.  What  is  the  pathology  of  aphthae? 

£.  They  are  either  little  tubercles  ulcerated,  or  small 
tumefied  glands. 


254  MUCOUS    SYSTEM. 

Q.  What  are  fungi  of  the  mucous  membranes? 

«/?.  They  are  thickenings  of  the  mucous  parietes. 
Q.  What  general  division  of  the  diseases  of  this  tissue 
do  you  make? 

«/?.   The  idiopathic  and  symptomatic. 

Q.  What  are  the  diseases  of  the  conjunctiva? 

A.   Ophthalmia  and  fungus. 

Q.  Name  the  diseases  of  the  pituitary  membrane. 

*ft.  They  are  coryza,  ozoena,  polypi,  abscess  in  the 
malar  antrum,  and  inflammation  of  the  Eustachian  tube, 
and  haemorrhage. 

Q.  What  renders  the  pituitary  membrane  so  liable  to 
haemorrhage? 

*#    Its  great  vascularity. 

Q.  How  do  you  divide  polypi  of  this  membrane? 

«#.  Into  the  vesicular  and  hard;  the  last  is  most  dan- 
gerous. 

Q.  Is  the  mucous  membrane  of  the  mouth  prone  to  in- 
flame? 

e/#.  It  is  less  so  than  any  of  the  mucous  surfaces. 

Q.  What  persons  are  most  liable  to  aphthse? 

«#.  Children,  and  those  who  at  any  age  have  chronic 
diseases. 

Q.  There  is  another  disorder  to  which  the  mucous 
membrane  of  the  mouth  is  little  disposed,  what  is  it? 

t/2.  Haemorrhage  rarely  proceeds  from  it. 

Q.  What  active  sympathy  does  this  mucous  surface 
maintain? 

*fl.  That  of  the  tongue  with  the  stomach. 

Q.  To  what  are  the  foul  tongue  and  the  black  tongue 
owing? 


MUCOUS    SYSTEM.  255 

t#.  To  disease  of  the  subjacent  glands  of  the  mucous 
membrane  or  of  the  tongue. 

Q.  What  affection  most  frequently  appears  on  the  mem- 
brane of  the  pharynx? 

«#.   Venereal  ulceration. 

Q.  Name  the  principal  diseases  of  the  laryngeal  mu- 
cous surface. 

t/2.   Croup,  and  laryngeal  phthisis. 

Q.  Where  is  the  force  of  the  last  disease  expended? 

t#.  Originating  in  the  mucous  membrane,  it  fixes  on  and 
destroys  the  arytenoid  cartilages  by  ulceration. 

Q.  What  are  the  general  pathological  states  of  pulmo- 
nary catarrh? 

Ji.   Those  of  acute  and  chronic  mucous  inflammation. 

Q.  Name  another  frequent  disease  of  the  pulmonary 
mucous  membrane. 

*fl.   Haemoptysis,  which  ends  in  phthisis. 

Q.  What  are  the  diseases  of  the  gastric  mucous  mem- 
brane ? 

*ft.  It  has  its  catarrhal  state.  You  find  also  the  haema- 
temesis,  and  cancer;  if  indeed  the  last  arises  from  the  mu- 
cous surface. 

Q.  To  what  affections  is  the  intestinal  mucous  mem- 
brane liable? 

«#.  To  acute  and  chronic  diarrhoea  and  dysentery. 
Hemorrhage  does  not  often  occur  there. 

Q.  In  what  part  of  the  intestinal  tract  do  you  find 
cancer? 

«#.  Chiefly  about  the  rectum. 
Q.  Whence  is  tympanites? 

«/?.  It  is  a  collection  of  air  in  the  bowels;  the  gas  is  se- 
creted from  the  mucous  membrane. 


256  MUCOUS    SYSTEM. 

Q.  There  are  two  causes  for  gonorrhoea,  what  are 
they? 

ifl.  The  disease  is  from  ordinary  and  specific  causes. 
Gonorrhoea  from  filth,  illustrates  the  first;  that  from  syphi- 
lis, the  second. 

Q.  Where  is  gonorrhoea  seated  ? 

tfi.  It  is  a  disease  of  the  mucous  glands.  Recollect  the 
fluor  albus  in  females. 


(     ->57     ) 


SEROUS  SYSTEM. 

Q.  Why  is  it  so  called  ? 

.#.  From  the  kind  of  fluid  that  constantly  lubricates 
one  of  its  surfaces. 

Of  the  Extent,  Forms,  and  Fluids  of  the  Serous  System, 

Q.  Name  the  principal  serous  membranes. 

^?.  They  are  the  peritoneum,  the  pleura,  the  pericar- 
dium, the  arachnoides,  the  tunica  vaginalis  testis. 

Q.  What  form  does  the  serous  tissue  assume  ? 

Jl.   Always  that  of  membrane. 

Q.  What  distinctive  observation  here  arises  between 
the  serous  and  mucous  membranous  expansions? 

•#.  The  serous  membranes  are  spread  out  over  the  ex- 
ternal surface  of  the  organs;  the  mucous  membranes  line, 
the  interior  of  the  organs. 

Q.  Which  is  the  most  extensive  system  of  the  two? 

&.  The  serous  tissue. 

Q.  Mention  another  distinguishing  trait  in  these  two 
tissues. 

•#.  The  serous  tissues  pour  out,  by  exhalation,  an  albu- 
minous fluid;  the  mucous  tissues  secrete  mucus. 

Q.  Does  the  serous  surface  exceed  the  cutaneous  in 
extent? 

A.  It  does;  it  is  even  probable  that  the  serous  exhala- 
tion exceeds  in  quantity  the  fluid  prepared  on  the  cuta- 
neous and  pulmonary  surfaces  collectively. 

33 


258  SEROUS    SYSTEM, 

Q.   Is  serum  an  excrementitious  fluid? 

*#.  Entirely  the  reverse;  it  is  recrementitious. 

Q.  What  is  the  form  of  each  serous  membrane? 

«#.  That  of  a  sac  without  an  opening;  like  a  double 
night-cap  folded  within  itself. 

Q.  Into  how  many  parts  can  a  serous  membrane  be 
divided? 

«/?.  Remembering  that  it  is  continuous,  it  may  be  di- 
vided into  the  membrane  that  lines  the  inner  surface  of  a 
cavity,  and  that  which  invests  the  outer  surface  of  the  or- 
gans contained  in  that  cavity.  Take  for  illustration  the 
costal  pleura  and  the  pulmonary  pleura. 

Q.  What  do  you  understand  by  the  free  and  adherent 
surfaces  of  the  serous  membranes? 

t/2.  The  adherent  surface  covers  the  organs;  the  free 
surface  the  interior  of  the  sac. 

Q.   What  is  Bichat's  doctrine  of  organic  life? 

Jl.  That  each  organ  has  its  peculiar  life,  resulting  from 
a  particular  modification  of  its  vital  forces;  this  modifica- 
tion establishing  one  in  the  circulation,  nutrition.and  tem- 
perature of  each  organ. 

Q.  Is  any  influence  on  these  separate  lives  produced  by 
the  serous  investitures? 

Jl.  The  serous  membranes  so  insulate  the  organs  as  to 
favour  the  theory  and  operation  of  separate  lives. 

Q.  What  influence  have  the  serous  investments  on  the 
spread  of  diseased  action  from  one  organ  to  another? 

Jl.  They  are  unfavourable  to  such  extension  of  morbid 
action. 

Q.  In  what  pathological  point  do  the  serous  and  mucous 
tissues  conspicuously  differ? 

•#.   In  their  respective  dispositions  to  form  adhesions 


SEROUS    SYSTEM,  259 

You  will  observe  that  the  serous  surfaces  are  as  prone  to 
adhere,  as  you  have  seen  the  mucous  tissues  reluctant  to 
do  so. 

Q.  Where  are  these  serous  adhesions  most  frequently 
found? 

•ft.  They  occur  most  frequently  in  the  pleura.  They 
are  seldom  met  with  in  the  tunica  arachnoides. 

Q.  These  adhesions  vary  much;  will  you  describe  some 
of  these  varieties  ? 

«#.  Sometimes  they  are  so  extensive  and  close  as  to 
form  but  one  membrane;  again  they  are  loose  and  easily 
separable.  Then  you  will  see  elongations  from  the  fixed 
to  the  free  serous  surface,  these  elongations  have  canals  in 
them.  Bichat  thinks  these  elongations  are  original  for- 
mations, not  the  result  of  diseased  action;  and  lastly,  there 
are  adhesions  of  cellular  layers,  without  these  canals. 

Q.  What  is  to  be  observed  of  the  connexions  of  the  se- 
rous and  mucous  membranes  in  disease? 

t/2.  That  as  their  organization  differs,  and  as  their  vital 
forces  vary,  they  are  distinct  and  unconnected  in  disease. 

Q.  What  is  the  nature  of  the  serous  fluids? 

«/?.  It  is  a  dew,  a  halitus  in  health;  the  serum  is  albu- 
minous in  its  nature.  In  disease  it  is  found  changed  to 
pus,  albuminous  flakes,  bloody,  and  fluids  of  various  other 
colours. 

Organization  of  the  Serous  System. 

Q.  What  are  the  characters  of  the  organization  of  serous 
tissue? 

Jl.  It  is  a  single,  transparent,   whitish,  shining  mem- 


260  SEROUS    SYSTEM, 

brane.  It  differs  from  the  mucous  tissue  in  having  but  a 
single  layer. 

Q.  What  is  the  nature  of  this  membrane  ? 

«#.  It  is  cellular.  It  has  the  common  organization  of 
the  cellular  tissue,  without  any  peculiar  structure;  it  has 
not,  for  instance,  any  peculiar  structure,  such  as  the  mus- 
cles have  in  their  fibrin,  or  as  the  bones  have  in  their  phos- 
phate of  lime. 

Q.  What  proof  have  you  that  this  serous  tissue  is  cel- 
lular? 

t#.  It  is  proved  to  be  so  by  the  identity  of  function  and 
that  of  disease;  it  is  cellular,  because  it  is  inflated  or  infil- 
trated by  air;  and  in  the  process  of  maceration,  the  absence 
of  fibrous  structure  proves  negatively  the  identity  of  the 
serous  and  cellular  tissues. 

Q.  What  gives  to  some  parts  of  the  body  a  deeper 
black  in  putrefaction  than  others? 

t#.  The  blackness  in  putrefaction  depends  on  the  quan- 
tity of  blood  in  the  putrefied  part. 

Q.  In  what  pathological  points  do  the  serous  and  cel- 
lular tissues  differ? 

<ft.  In  the  first,  being  subject  to  a  slow  inflammation 
producing  tubercles,  and  in  the  circumstance  that  the  se- 
rous pus  differs  from  that  in  the  cellular  texture. 

Q.  What  are  the  parts  common  to  the  serous  mem- 
branes? 

Ji.  Exhalents,  absorbents,  and  blood-vessels. 

Q.  Are  the  blood-vessels  numerous? 

Jl.   No;  in  health  they  are  few  and  small. 

Q.  What  shows  the  existence  of  exhalents  in  this  tis- 
sue ? 

«/?.  Expose  a  serous  surface  in  the  living  animal,  wipe 


SEROUS    SYSTEM.  261 

it  dry,  and  you  will  very  soon  see  it  covered  with  new 
serum  from  the  exhalents. 

Q.  How  will  you  have  a  view  of  the  absorbents? 

A.  Macerate  a  beef's  heart  for  several  hours  in  water, 
and  you  will  see  its  serous  surface  covered  with  absorb- 
ents; this  among  other  modes  of  showing  them. 

Q.  What  varieties  of  organization  do  the  serous  tissues 
present  ? 

t#.  Perhaps  each  membrane  has  its  peculiar  structure. 
There  is  the  thin,  soft,  tender  arachnoides;  the  thick, 
compact  peritoneum. 

Q.  What  pathological  principle  do  you  derive  from  this 
variation  in  structure? 

<ft.  Diversity  in  disease;  greater  or  less  liability  to  acute 
and  chronic  inflammation. 

Q.  To  what  peculiar  affection  is  the  pericardium  sub- 
ject? 

*ft.  To  the  formation  of  thick  white  layers  on  its  inter- 
nal surface;  such  as  are  not  found  elsewhere  in  the  serous 
surface. 

Q.  What  tissues  are  exclusively  the  seats  of  serous  ef- 
fusion ? 

£.  The  serous  and  synovial  textures. 

Properties  of  the  Serous  System. 

\.  Properties  of  Texture. 

Q.  Do  the  serous  membranes  manifest  much  extensi- 
bility ? 

«#.  From  the  dilatations  they  undergo,  you  would  sup- 


262  SEROUS    SYSTEM. 

pose  the  tissue  was  very  extensible.  Not  so,  however;  for 
•  in  these  dilatations  the  folds  of  the  serous  membranes  are 
developed,  or  there  is  a  kind  of  displacement  of  these 
membranes.  This  is  the  case  in  ascites  and  pregnancy. 
The  texture  is  but  slightly  distensible. 

Q.  Under  what  circumstances  are  these  displacements 
of  the  serous  membranes  painful? 

«#.   They  are  severely  so  in  inflammation. 

Q.  What  have  you  to  say  of  the  contractility  of  this 
texture  ? 

Jl.  That  it  is  evident,  though  not  very  great.  It  is 
evident  in  hydrocele  and  ascites  after  the  water  is  evacu- 
ated. After  long  and  repeated  distention  these  membranes 
lose  their  contractility. 

2.   Vital  Properties. 

Q.  What  vital  properties  predominate  in  these  tissues? 

«#.  Insensible  organic  contractility  and  organic  sensi- 
bility. The  other  vital  properties  are  wanting. 

Q.  What  effect  has  disease  on  these  properties? 

t/2.  By  it  they  are  so  exalted  as  to  give  acute  pain,  and 
the  texture  of  these  membranes  is  readily  changed. 

Q.  When  the  serous  tissues  sympathize  with  affections 
of  other  organs,  where  is  the  effusion  of  serum  found? 

«#.  In  the  serous  cavity  nearest  the  affected  organ;  as 
in  the  chest  when  the  heart  is  diseased. 

Q.  What  distinction  does  Bichat  draw  between  idiopa- 
thic  and  sympathetic  serous  disorder? 

«#.  In  the  idiopathic  disorder,  the  exhalents  and  ab- 
sorbents of  the  texture  are  in  a  diseased  state;  in  the  sym- 


SEROUS    SYSTEM.  263 

pathetic  they  are  not.  In  the  idiopathic  the  serum  is  greatly 
altered  in  colour,  consistence,  &c.;  in  the  sympathetic  the 
serum  is  healthy. 

Development  of  the  Serous  System. 

Q.  How  does  the  development  of  the  serous  tissues  pro- 
gress? 

«#. .  In  proportion  to  that  of  the  organs  they  cover. 

Q.  Which  is  earliest  and  most  rapidly  developed? 

«/?.  The  arachnoides,  and  hence  hydrocephalic  effusion 
is  so  frequent  in  infancy:  next  in  development  is  the 
pleura,  hence  the  frequency  of  pleurisy  in  youth. 

Q.  What  alteration  in  form  often  takes  place  in  diseases 
of  the  serous  tissues? 

Jl.  They  become  in  some  cases  much  thicker,  and  in 
others  thinner  than  in  their  healthy  state. 

Q.  Why  is  it  of  practical  importance  to  know  the  dis- 
placements of  the  serous  membranes? 

«/?.  Because  in  these  displacements  there  is  a  change  in 
the  relations  of  parts. 

Q.  What  is  the  nucleus  of  the  various  tubercles,  tu- 
mours, &c.  which  are  seen  in  such  numbers  on  the  serous 
membranes? 

«#.  The  nucleus  is  formed  by  a  concretion  of  albumen 
which  becomes  vascular. 

Q.  In  what  points  do  hydatids  and  cysts  differ? 

t/?.  Cysts  are  connected  with  surrounding  parts  by  cel- 
lular substance  and  blood-vessels;  hydatids  are  not.  The 
parietes  of  cysts  have  a  degree  of  consistence  which  hyda- 
tids do  not  exhibit.  Hydatids  have  granular  substances 
on  some  part  of  their  surface ;  cysts  have  not. 


264  SEROUS    SYSTEM 


PATHOLOGY  OF  THE  SEROUS  TISSUE, 

Q.  Give  a  general  division  of  the  serous  diseases. 

«#.  They  are  idiopathic  or  essential,  and  sympathetic, 

Q.  What  is  the  most  frequent  disease  of  this  tissue? 

«#.  Inflammation,  acute  and  chronic. 

Q.  Are  all  the  membranes  equally  disposed  to  inflame  ? 

A.  No;  they  exhibit  this  disposition  in  the  following 
order,  viz.  the  pleura,  peritoneum,  pericardium,  tunica 
vaginalis,  and  the  arachnoid  membrane. 

Q.  What  is  the  most  frequent  cause  of  serous  inflam- 
mation? 

«#.   Suppressed  perspiration. 

Q.  What  conspicuous  symptoms  attend  serous  inflam 
mation? 

t#.   A  peculiar  lancinating  pain  and  great  fever. 

Q.  What  is  the  common  termination  of  serous  inflam- 
mation? 

*ft.  It  is  by  adhesion;  and  this  takes  place  by  a  new 
membrane,  or  by  an  elongation  of  fibres,  or  by  contact 
and  blending  of  the  surfaces  of  the  membranes. 

Q.  What  is  the  order  of  liability,  in  the  serous  mem- 
branes, to  this  adhesion? 

•ft.  It  is  as  follows:  the  pleura  is  most  given  to  form 
adhesion,  next  the  peritoneum,  then  the  pericardium,  the 
tunica  vaginalis,  and  lastly  the  arachnoides. 

Q.  As  serous  inflammation  terminates  in  effusion  and 
suppuratibn,  what  fluids  are  found  in  the  sacs  ? 

Jl.  It  sometimes  resembles  milky  serum,  sometimes  it 
has  flakes  swimming  in  the  serum;  the  serum  is  again 
bloody;  and  lastly  there  is  pus. 


SEROUS    SYSTEM.  265 

Q.  What  indicates  the  formation  of  pus  in  the  serous 
sacs? 

.#.  Alteration  of  the  pain  from  its  acuteness;  there  is  a 
sensation  of  weight,  and  the  symptomatic  constitutional 
signs  of  the  suppurative  process. 

Q.  In  which  serous  tissue  does  gangrene  oftenest  ap- 
pear? 

•ft.  In  the  peritoneum;  but  observe  that  the  blackest 
peritoneum  is  not  always  the  most  gangrenous. 

Q.  There  is  another  important  and  common  termina- 
tion of  acute  serous  inflammation  which  has  not  been 
named. 

t/tf.  It  is  the  chronic  inflammation.  You  will  recollect 
that  this  is  very  often  an  original  form  of  disease,  as  well 
as  a  consequence  of  the  acute  serous  inflammation. 

Q.  Is  chronic  inflammation  of  the  serous  membranes 
habitually  extended  from  one  to  another? 

,#.  Very  rarely ;  but  observe  the  continuous  affections 
of  the  mucous  membranes. 

Q.  What  is  the  character  of  die  pain  in  chronic  inflam- 
mations of  the  serous  membranes? 

«#.   It  is  an  obscure,  pricking  pain. 

Q.  What  is  the  most  interesting  pathological  result  of 
this  chronic  inflammation  of  the  serous  membranes? 

*#.  Dropsy;  the  correct  pathology  of  which  is,  that  it 
is  a  chronic  inflammation  of  the  serous  membranes. 

Q.  Can  you  point  out  a  difference  in  the  symptomatic 
and  idiopathic  dropsies? 

.#.  When  dropsy  is  symptomatic  of  an  organic  disease, 
the  cellular  tissue  is  infiltrated;  but  when  idiopathic,  it  is 
in  the  serous  cavities  alone. 

Q.   What  fluids  are  deposited  in  dropsy? 
.  34 


266  SEROUS    SYSTEM. 

*ft.  Serum,  bloody  serum,  greenish  serum,  serum  with 
flakes,  blood  itself. 

Q.  What  is  the  autopsic  demonstration  in  the  serous 
tissues  after  chronic  inflammation? 

*fl.   They  are  slightly  thickened  and  swollen. 

Q.  There  is  yet  another  pathological  state  of  the  serous 
membranes. 

*ft.  Yes.  They  are  the  seats  of  miliary  eruption ;  this  is 
especially  true  of  the  peritoneum.  In  these  cases  the  mem- 
brane is  red,  an$  the  disease  arises  from  repelled  eruptions 
and  from  cold. 

Q.  What  is  the  first  pathological  process  in  the  course 
of  serous  inflammation  ? 

«/?.  It  is  to  check  the  exhalation  of  serum. 

Q.  What  is  the  most  frequent  sympathetic  disease  of 
the  serous  membranes? 

•A.  Dropsy;  which  arises  either  from  the  disease  of  the 
organ  invested  with  serous  membranes,  or  from  the  debi- 
lity of  protracted  organic  disease,  as  consumption.  The 
last  are  passive  exhalations  of  serum. 

Q.  What  serous  membranes  are  most  obnoxious  to 
symptomatic  dropsies? 

£.  The  peritoneum,  the  pleura,  and  the  pericardium, 
in  the  order  in  which  they  are  named. 

Q.  What  are  the  diseases  of  the  pleura  ? 

A.  Acute  and  chronic  inflammation. 

Q.  Why  is  acute  pleurisy  so  frequent? 

A.  This  frequency  is  occasioned  by  proximity  to  the 
lungs,  which  are  so  constantly  exposed  to  the  air ;  another 
cause,  the  susceptibility  of  the  pleura  to  take  on  disease 
from  suppressed  perspiration. 

Q.  With  what  is  pleurisy  apt  to  be  confounded? 


SEKOUS    SYSTEM-  3()7 

»fl.   With  peripneumonia. 

Q.   How  are  they  distinguished? 

«/?.  The  pain  in  pleurisy  is  acute,  in  peripneumony  it  is 
obtuse  or  deep-seated;  in  pleurisy  external  pressure  gives 
pain,  but  it  is  not  so  in  peripneumony.  The  dyspnoea  in 
pleurisy  is  attended  with  acute  pain,  and  full  inspiration 
is  impossible  in  peripneumony,  owing  to  the  oppression 
and  the  obtuse  pain.  The  face  in  peripneumony  is  very 
red,  even  livid ;  in  pleurisy  it  has  the  ordinary  febrile  red- 
ness. The  pulse  is  full,  strong,  and  hard  in  pleurisy,  but 
in  peripneumony  it  is  oppressed,  and  not  necessarily  hard 
or  full.  Lastly,  auscultation  gives  obscure  sound  in  pe- 
ripneumony, not  so  in  pleurisy.* 

Q.  What  does  the  protracted  pain  in  pleurisy  indicate? 

«#.  The  continuance  of  inflammation ;  for  inflammation 
does  not  suddenly,  but  gradually  subside. 

Q.   What  are  the  signs  of  suppuration  in  pleurisy? 

«/?.  Diminution  of  force  and  increase  of  frequency  in 
the  pulse;  irregular  chills,  hectic  flush,  sweats,  alteration 
of  pain  from  acuteness  to  a  sense  of  weighty  pain,  expan- 
sion of  the  affected  side. 

Q.  What  two  modes  are  important  in  ascertaining  the 
presence  of  pus? 

»#.  Percussion  is  one;  and  pressure  on  the  epigastrium, 
which,  by  throwing  the  pus  up,  occasions  a  sense  of  suffo- 
cation. 

*  At  the  commencement  of  pleurisy,  before  any  adhesions  take  place, 
or  fluid  is  effused,  the  sound  on  auscultation  is  natural;  but  when  the 
effusion  is  considerable  from  the  commencement,  or  becomes  so  dur- 
ing the  progress  of  the  disease,  the  sound  is  dull.  If  the  effusion  is 
moderate,  the  sound  is  dull  in  the  lower  part  of  the  thorax,  both  la- 
terally and  posteriorly. 


268  SEROUS    SYSTEM. 

Q.  How  does  chronic  pleurisy  differ  from  phthisis? 

»#.  The  cough  is  drier,  there  are  no  night  sweats;  the 
pain  is  fixed,  and  in  pleurisy  there  is  local  dropsy  with  its 
indications ;  whereas,  in  phthisis  there  is  cellular  dropsy. 

Q.  What  effects  have  diseased  lungs  on  the  pleura? 

Ji.   They  induce  chronic  pleurisy. 

Q.  Are  there  any  certain  indications  of  effusion  in  the 
pericardium? 

.#.  If  any  one  will  distinguish  it  from  surrounding  dis- 
ease, it  is  pressure  on  the  epigastric  region,  which  throw- 
ing up  the  fluid,  occasions  suffocation. 

Q.  What  are  the  terminations  of  pericarditis? 

t#.  In  adhesion,  suppuration,  in  effusion  of  serum,  and 
in  a  greatly  increased  thickness. 

Q.  Is  the  peritonitis  as  local  as  the  pain  in  that  dis- 
ease? 

•ft.  Although  the  pain  may  be  locally  very  acute,  yet 
the  inflammation  is  diffused.  It  is  the  same  case  with 
pleurisy,  in  which  the  pain  is  pointed,  although  the  in- 
flammation is  extensive. 

Q.  Whence  does  the  vomiting  in  peritonitis  arise  ? 

«#.  It  is  sympathetic,  not  from  irritating  gastric  con- 
tents. 

Q.  Mention  a  very  remarkable  distinction  between  pe- 
ritonitis and  dysentery. 

«#.  In  peritonitis  the  bowels  are  costive  or  natural,  in 
dysentery  the  stools  are  characteristic  of  mucous  irrita- 
tion. 

Q.  How  does  peritonitis  terminate? 

«#.  In  adhesions  of  the  intestines  to  each  other,  in 
serous  effusion,  in  the  formation  of  pus,  and  in  gangrene 

Q.  Where  are  these  adhesions  most  conspicuous? 


SEROUS    SYSTEM.  269 

*#.  In  the  large  intestines.  I  have  seen  all  the  intes- 
tines perfectly  glued  together  by  adhesions*  in  chronic  pe- 
ritonitis; they  could  not  be  separated. 

Q.  To  what  is  the  abdominal  swelling  in  puerperal 
fever  owing? 

*tf.  To  a  distention  of  the  cellular  texture  subjacent  to 
the  serous  membranes. 

Q.  What  symptoms  are  peculiar  to  puerperal  perito- 
nitis? 

./?.  The  condition  of  the  breasts,  and  the  lochial  dis- 
charge. 

Q.  Whence  does  ascites  originate? 

*#.  From  idiopathic  and  symptomatic  chronic  inflam- 
mation of  the  peritoneum.  The  hydrocele  is  from  acute 
or  chronic  inflammation  of  the  tunica  vaginalis. 

Q.  What  are  the  diseases  of  the  arachnoid  membrane? 

Ji.  Phrenitis,  hydrocephalus. 

Q.  Are  there  not  other  seats  of  these  diseases  in  the 
brain  than  the  arachnoid  membrane? 

*fl.  As  the  other  tissues  in  the  cranium  are  not  suscepti- 
ble of  inflammation,  the  answer  is  in  the  negative. 


(    270    ) 


SYNOVIAL  SYSTEM. 

Q.  In  what  respects  does  this  system  resemble  the  se- 
rous? 

£.  In  its  form,  the  sac  without  opening;  in  its  texture, 
which  is  cellular ;  and  in  its  functions,  those  of  exhalation 
and  absorption. 

Q.  In  what  respects  do  they  differ? 

*#.  In  the  composition  of  their  fluids.  Dropsical  affec- 
tions of  the  cellular  and  serous  tissues  do  not  induce  sy- 
novial  dropsies,  and  vice  versa.  The  synovial  tissues  are 
not  so  subject  to  tubercular  diseases  as  the  serous.  Adhe- 
sions do  not  take  place  in  the  synovial  tissues  as  in  the  se- 
rous. The  synovial  membranes  are  not  locomotive  as  the 
serous  were  said  to  be.  The  fluids  of  synovial  and  general 
dropsy  are  not  alike. 

Q.   How  is  the  synovial  system  divided  ? 

*#.  Into  that  of  the  joints,  and  that  of  the  tendinous 
grooves. 

1.   Of  the  Articular  Synovial  System. 

Q.  How  are  the  fluids  of  the  system  separated  from  the 
blood? 

%#.  In  three  ways.  By  secretion  from  a  gland,  inter- 
mediate to  the  blood-vessels,  which  bring  the  blood,  and 
the  excretory  which  carries  off  the  secreted  fluid;  by  ex- 
halation, where  there  is  a  direct  continuity  of  blood-ves- 


SYNOVIAL    SYSTEM.  271 


sel  and  exhalent,  without  an  intervening  gland;  by  t 
dation,  which  takes  place  after  death. 

Q.  Why  do  you  object  to  the  formation  of  synovial 
fluid  by  secretion? 

«#.  Because  the  glands,  ducts,  and  other  apparatus  of 
secretion  do  not  .exist. 

Q.  Why  do  you  oppose  the  doctrine  of  the  transuda- 
tion  of  the  synovia? 

«/?.'  Because  the  operation  of  transudation  is  in  opposi- 
tion to  vitality,  and  compatible  only  with  death  in  the 
vessels. 

Q.   Can  you  maintain  the  doctrine  of  exhaled  synovia? 

*ft.  It  is  reasonable  to  adopt  the  doctrine  of  exhalation, 
because  the  serous  and  synovial  fluids  resemble  each  other, 
being  both  albuminous.  The  use  of  the  two  fluids  is  the 
same,  both  being  destined  to  lubricate  surfaces  admitting 
of  free  motions.  The  serous  and  synovial  fluids  are  both 
liable  to  be  suppressed  by  inflammation.  The  synovial 
membranes,  when  they  do  adhere,  in  this  resemble  the 
serous.  The  two  tissues  are  both  liable  to  dropsy;  and 
finally,  both  fluids  are  absorbed. 

Q.  What  is  the  appearance  of  the  synovial  fluid? 

«/?.  It  is  a  white,  viscid,  transparent,  ropy,  unctuous 
fluid,  supposed  to  have  a  peculiar  kind  of  albumen. 

Q.   What  is  the  form  of  the  synovial  membrane? 

«/?.  A  sac  without  an  opening,  spread  on  the  articular 
surfaces. 

Q.  How  is  this  form  ascertained  ? 

JL.  By  dissection,  and  by  the  appearance  of  the  mem- 
brane when  thickened  by  disease. 

Q.  What  difference  appears  between  the  fibrous  cap- 
sules and  the  synovial  membranes? 


272 


SYNOVIAL    SYSTEM. 


A.  They  are  totally  distinct,  in  function  and  organiza- 
tion, from  those  capsules,  which  last  are  found  only  in  one 
or  two  articulations. 

Q.  What  are  the  red  fatty  bunches  found  about  the  ar- 
ticulations? 

•ft.  They  are  points  at  which  the  blood-vessels  going  to 
the  synovial  membrane  divide  most  minutely:  but  they 
are  not  glands,  as  has  been  supposed. 

Q.  What  properties  of  texture  and  of  life  belong  to  this 
synovial  tissue? 

.#.  Slow  extensibility,  organic  sensibility  and  insensi- 
ble organic  contractility.  In  disease  the  organic  is  exalt- 
ed to  animal  sensibility,  producing  pain. 

Q.  What  experiment  proves  the  presence  of  fibrous 
capsules  about  a  joint? 

A.  Twist  a  joint  where  these  capsules  are,  and  there  is 
much  pain ;  but  where  the  synovial  membrane  exists  alone, 
there  is  not  this  pain  from  twisting  the  joint. 

Q.  Are  the  sympathies  of  the  synovial  tissue  active? 

«#.  On  the  contrary  they  are  few  and  weak. 

Q.  What  is  the  function  of  this  texture? 

«#.  To.  exhale  synovia  for  the  lubrication  of  the  joints  ? 

Q.  At  what  period  of  life  does  this  tissue  bear  the 
greatest  proportional  development? 

Jl.  In  the  foetus  and  the  infant;  for  the  reason  that  the 
articulations  are  larger  in  a  cartilaginous  than  in  their 
osseous  state. 

2.   Synovial  System  of  the  Tendons. 

Q.  Where  is  this  found? 

«#.  In  the  tendons  of  the  extremities,  but  not   in  ti>< 
trunk. 


SYNOVIAL    SYSTEM. 


273 


Q.  What  general  observations  have  you  to  make  on  this 
tissue? 

Jl.  That  in  its  organization,  properties,  functions,  sym- 
pathies, it  resembles  precisely  the  articular  synovial  sys- 
tem. 

Q.  What  do  you  mean  by  synovial  fringes? 

A.  They  are  elongations  and  duplicatures  of  the  mem- 
branes, from  which  the  synovia  is  almost  exclusively  ex- 
haled. 

Q.  Are  there  not  points  of  difference  in  the  serous  and 
synovial  systems,  besides  those  already  stated? 

t#.  The  serous  tissues  have  more  blood-vessels,  more 
lymphatic,  and  apparently  fewer  laminae. 


(    274    ) 


GLANDULAR  SYSTEM. 

Q.  How  do  you  define  a  gland? 

«#.  It  is  a  body  from  which  flows,  by  one  or  many  ducts, 
a  fluid,  which  this  body  separates  from  the  blood  received 
by  vessels  which  go  to  it. 

Q.  What  important  peculiarity  is  found  in  this  system? 

«#.  That  the  texture  peculiar  to  it  is  not  precisely  the 
same  in  all  the  organs  that  compose  the  system.  The  tex- 
ture of  the  liver  differs  from  that  of  the  kidney. 

Q.  Name  the  glands. 

t#.  Those  on  the  head  are,  the  salivary,  the  lachrymal, 
the  meibomeian  and  ceruminous  of  the  ear,  and  the  amyg- 
dala. On  the  thorax,  the  mammae.  In  the  abdomen  the 
liver,  pancreas  and  kidneys.  In  the  pelvis,  the  prostate 
and  testicles.  On  the  trunk  and  face  the  mucous  glands. 

Q.  Are  there  glands  on  the  extremities? 

t/2.  There  are  none. 

• 

Situation,  Forms,  Division,  Sec.  of  the  Glandular  Sys- 
tem. 

Q.  What  is  to  be  observed  of  the  position  of  these 
glands  ? 

«/2.  They  are  in  two  situations,  sub-cutaneous,  and  deep- 
seated. 

Q.  Does  the  motion  communicated  to  the  glands  by  the 
neighbouring  parts,  induce  their  excretion? 


GLANDULAR    SYSTEM.  275 

A.  It  does  not.  That  operation  is  the  result  of  vital  ac- 
tion; still  the  motion  given  to  some  glands  may  be  acces- 
sory to  excretion. 

Q.  Under  what  circumstances  is  this  accessory  motion 
necessary  ? 

«#.  It  is  found  wherever  the  parietes  of  the  organ  are 
not  very  powerful. 

Q.  Besides  the  division  of  glands  into  sub-cutaneous 
and  deep-seated,  there  is  another,  what  is  it? 

V?.  Into  single  and  double  glands.  The  liver  is  a  single 
gland;  the  kidneys  are  double,  in  pairs. 

Q.  Is  there  the  exact  symmetry  in  two  glands  of  the 
same  pair  as  is  found  in  the  organs  of  animal  life? 

«#.  There  is  not;  because  the  harmony  of  action  in  ani- 
mal life  requires  the  utmost  exactness. 

Q.  What  circumstance  materially  controls  these  varie- 
ties of  form  in  the  glandular  tissue? 

*fl.  The  fact  of  their  being  invested  by  a  strong  mem- 
brane has  great  influence  in  this  respect.  The  liver,  which 
is  contained  in  a  membrane,  has  much  fewer  varieties  than 
the  lachrymal,  or  the  salivary,  which  are  without  such  in- 
vestment. 

Organization  of  the  Glandular  System. 

Q.  In  what  is  the  texture  of  the  glands  peculiar? 

«#.  The  oblique  or  longitudinal  fibrous  linear  arrange- 
ment met  with  in  the  muscular,  osseous,  nervous  tissues,- 
is  not  seen  at  all  in  the  glands.  They  are  agglomerated, 
and  slightly  united  by  cellular  texture. 

Q.   How  is  the  parenchyma  of  glands  to  be  divided? 

rf.   Into  three  forms. 


276  GLANDULAR    SYSTEM. 

Q.  What  are  they? 

A.  There  is  first,  the  glandular  parenchyma  with  larger 
lobes,  separated  from  each  other  by  cellular  substance; 
these  larger  lobes  are  resolved  into  smaller  lobes,  which 
are  agglomerated ;  and  these  smaller  lobes  are  composed 
of  glandular  grains. 

Q.  What  glands  are  thus  organized? 

*#.   The  pancreas,  the  salivary  and  lachrymal  glands. 

Q.  What  is  the  second  form  of  the  glandular  paren- 
chyma? 

•#.  It  is  that  of  glandular  bodies  connected  by  cellular 
substance  without  the  lobulated  structure  of  the  first  form. 

Q.  What  glands  are  examples  of  this? 

£.  The  liver  and  the  kidneys. 

Q.  Designate  the  third  form  of  the  glandular  paren- 
chyma. 

*#.  The  third  form  comprising  the  amygdalae  and  mu- 
cous glands  have  a  soft,  pulpy  parenchyma,  without  lobes 
or  grains. 

Q.  Is  the  organization  of  all  the  glands  included  in 
these  forms? 

»#.  It  is  not.  The  mammary  glands  and  the  testicles 
have  a  peculiar  texture. 

Q.  What  peculiar  effect  does  ebullition  produce  on  this 
glandular  texture? 

«#.  All  the  tissues  acquire  the  horny  hardening  in  the 
first  ebullition,  but  as  the  boiling  is  continued  they  be- 
come soft.  Now  the  glands  differ  from  the  textures  in 
this,  that  the  longer  they  are  boiled  the  harder  their  sub- 
stance becomes. 

Q.  What  is  the  origin  of  the  excretory  ducts? 

*#.   They  arise  as  capillaries,   one  from  each  glandular 


GLANDULAR    SYSTEM. 


277 


point  in  a  gland ;  they  unite  and  form  ducts.  These  excre- 
tory ducts  are  known  only  in  the  glandular  system. 

Q.  Is  the  number  and  arrangement  of  these  ducts  uni- 
form in  the  glands? 

•ft.  They  are  not  uniform  in  either  respect.  Some  glands 
excrete  by  several  ducts  which  do  not  communicate  with 
each  other;  this  you  see  illustrated  in  the  nipple.  There 
are  some  which  excrete  by  a  single  duct;  instances  of 
which  you  see  in  the  parotids,  the  sublingual  glands,  and 
the  pancreas.  There  is  a  third  set  of  glands  which  have 
reservoirs  for  their  secretions,  of  which  the  liver,  testicles 
and  kidneys  are  examples. 

Q.  Where  do  the  excretory  ducts  open? 
«/#.  They  all  empty  themselves  either  on  the  external 
surface,  or  on  the  mucous  membranes.     They  never  open 
on  cellular  or  serous  surfaces,  for  the  secreted  fluids  are 
all  intended  to  be  thrown  off  from  the  body. 

Q.  Can  secreted  fluids  be  introduced  into  the  blood- 
vessels with  safety? 

«,#.  They  may  be  thrown  in  through  the  veins,  or  the 
crural  artery;  but  not  through  the  carotids,  for  then  they 
make  a  fatal  impression  on  the  brain. 

Q.  What  lines  the  excretories  of  the  glands? 
*ft.  The  mucous  membrane. 

Q.  In  what  glands  is  there  the  greatest  abundance  of 
cellular  texture? 

*ft.  In  those  glands  which  have  the  organization  of  a 
granulated  white  parenchyma,  such  as  the  heart,  the  pan- 
creas, and  the  salivary  glands. 

Q.  In  what  glands  is  there  least  cellular  substance? 
A.   In  those  with  compact  parenchyma,  as  the  liver, 
kidney,  prostate  and  mucous  glands. 


278 


GLANDULAR    SYSTEM. 


• 


Q.  How  do  you  explain  the  coexistence  of  extensive 
disease  of  the  liver,  and  yet  a  secretion  of  healthy  bile? 

«#.  The  cellular  texture  of  the  organ  is  diseased,  while 
the  peculiar  glandular  structure  is  unaffected. 

Q.  There  are  two  causes  for  the  size  of  the  female 
breast,  what  are  they  ? 

*#.  It  may  be  large  from  the  size  of  the  gland,  and  from 
an  undue  portion  of  cellular  texture  is  another. 

Q.  How  do  the  glands  receive  their  arteries? 

Jl.  Those  not  invested  with  membranous  expansions 
receive  their  blood-vessels,  on  all  sides,  from  the  sur- 
rounding parts.  Those  which  have  membranous  cover- 
ings receive  these  vessels  at  one  point,  usually  in  a  fissure, 
and  they  enter  at  that  part  of  the  gland  which  is  least  ex- 
posed to  external  injury. 

Q.  What  are  the  ultimate  arterial  ramifications  in  a 
gland  ? 

«#.  Each  glandular  grain  receives  a  capillary  artery. 

Q.  Has  arterial  motion  any  other  effect  on  a  gland  than 
to  circulate  its  blood? 

A.  Yes;  it  communicates  an  internal  motion,  very  fa- 
vourable to  their  functions. 

Q.  How  does  disease  of  the  right  auricle  of  the  heart 
affect  the  liver  ? 

Ji.  By  obstructing  the  flow  of  blood  from  the  hepatic 
vein,  it  has  a  direct  congestive  influence  on  the  liver. 
Hence  at  least  one  cause  of  the  frequent  simultaneous  oc- 
currence of  diseased  heart  and  liver. 

Q.   In  what  glands  is  there  most  blood  ? 

»#.  It  is  in  greatest  quantity  in  the  liver  and  kidney; 
and  there  is  least  blood  in  the  pancreas,  salivary,  and  la- 
chrymal glands. 


GLANDULAR    SYSTEM,  279 

Q.  Are  the  nerves  of  the  glands  cerebral  or  ganglionic? 

.#.  Some  receive  cerebral  nerves,  such  as  the  salivary, 
lachrymal,  &c.  others  are  supplied  by  the  ganglions. 

Q.  Have  the  nerves  influence  on  secretion? 

<ft.  Whatever  influence  they  may  exercise,  it  is  not  es- 
sential ;  for  we  find,  in  many  instances,  that  secretion  goes 
on,  although  the  nerves  of  the  part  are  destroyed. 

Properties  of  the  Glandular  System. 
1.   Properties  of  Texture. 

Q.  To  what  extent  does  the  glandular  tissue  manifest 
properties  of  texture? 

•ft.  Extensibility  and  contractility  of  texture  exist  to  a 
very  limited  degree. 

2.    Vital  Properties. 

Q.  Have  the  glands  the  vital  properties  of  animal  life, 
to  any  great  degree? 

.#.  They  have  no  animal  contractility ;  but  some  of  the 
glands,  for  example,  the  testicles,  have,  when  pressed,  and 
others  have,  when  cut,  much  animal  sensibility. 

Q.   Is  the  pain  of  an  inflamed  gland  peculiar? 

«/?.  It  is  of  a  dull,  obtuse  character;  not  acute,  as  in  the 
cellular  texture,  nor  sharp  and  biting,  as  in  the  skin. 

Q.  What  as  to  their  properties  of  organic  life  ? 

*ft.  Inafcnsible  organic  contractility,  and  organic  sensi- 
bility exist  in  their  utmost  activity  in  the  glands.  These 
are  the  prominent  properties  that  control  the  functions, 


280 


GLANDULAR    SYSTEM. 


and  direct  the  pathology  of  glands.   Sensible  organic  con- 
tractility is  wanting. 

Q.   How  is  glandular  secretion  executed? 

*#.  The  blood  contains  the  materials  for  secretion;  the 
organic  sensibility  of  the  gland  elects  from  the  blood  the 
appropriate  elements,  and  the  insensible  organic  contrac- 
tility admits  or  rejects  the  fit  or  unfit  elements. 

Q.  On  what  principle  and  power  do  secretion,  exhala- 
tion, and  nutrition  depend? 

*#.  On  the  power  that  organic  sensibility  exercises  in 
the  gland,  to  select  the  materials  for  secretion;  in  the 
serous  membranes  for  exhalation;  and  in  all  the  organs 
for  nutrition. 

Q.  On  what  does  increased  or  diminished  secretion 
depend? 

«#.  On  an  exaltation  or  depression  of  the  predominant 
vital  forces  of  the  glands. 

Q.  How  is  it  that  each  gland  exercises  a  peculiar 
power  so  as  to  form  its  own  secretion,  as  the  liver  to  form 
bile,  the  kidneys  urine,  &c.? 

*ft.  The  power  depends  on  a  modification  of  the  organic 
sensibility  in  each  organ. 

Q.  Are  the  glands  easily  affected  by  impressions  from 
other  parts? 

t#.  These  foreign  impressions  constitute  the  passive 
sympathies  of  the  glands.  They  are  numerous,  and  they 
appear  in  health  and  in  the  course  of  disease. 

Q.  Designate  the  normal  passive  sympathies  of  the 
glands?  « 

t/?.  The  effect  of  aliments  on  the  salivary  glands,  the 
irritation  of  the  pituitary  membrane  producing  tears;  the 


GLANDULAR    SYSTEM.  281 

passage  of  food  into  the  duodenum  occasioning  a  flow  of 
bile.  These  all  take  place  on  the  mucous  surfaces,  and 
are  passive  normal  sympathies. 

Q.  You  have  said  that  the  passive  sympathies  of  the 
glands  were  frequently  abnormal  or  morbid. 

»#.  They  are  so.  Consider  how  the  liver,  kidneys,  and 
mucous  glands,  are  affected  by  diseases,  and  particularly 
the  influence  of  diseased  stomach  on  the  mucous  glands  of 
the  tongue. 

Q.  How  do  you  explain  the  effects  of  grief  on  the 
glands  of  the  eye? 

•fl.  The  first  impression  of  grief  is  on  the  epigastric 
region,  and  with  this  region  the  lachrymal  glands  sympa- 
thize. 

Q.  What  glands  are  least  disposed  to  assume  abnormal 
sympathetic  action? 

•ft.  The  testicles  and  prostate  glands,  because  their 
functions  are  insulated  from  the  rest.  But  as  the  greater 
number  of  the  other  glands  are  intimately  connected  with 
the  process  of  digestion,  which  process  supports  the  very 
existence  of  all  the  organs;  for  this  reason  we  say  that 
these  glands  sympathize  more  readily  and  fully  with  all 
the  organs. 

$.  Are  the  active  sympathies  of  the  glandular  system 
numerous? 

4#.  They  are  not  so  much  so  as  the  passive.  The  most 
remarkable  is  the  effect  of  the  development  of  the  testi- 
cles on  the  voice.  The  diseases  of  the  generative  system 
or  seminal  organ  has  much  effect  on  the  pulmonary  mu- 
r.ous  system. 

Q.   You  have  said  that  each  gland  has  its  modification 
of  vitality,  whence  does  this  arise  ? 
'     38 


282  GLANDULAR    SYSTEM. 

•fl.  From  peculiarity  of  texture.  From  these  modifi- 
cations of  vitality  and  peculiarities  of  textures,  it  results 
that  the  different  glands  have  certain  substances  in  relation 
to  them.  From  these,  likewise,  arise  the  peculiar  sym- 
pathies of  each  gland,  the  particular  character  of  the  in- 
flammation of  each  gland,  and  their  predispositions  to  dis- 
ease. 

Q.  Give  some  examples  of  the  exclusive  relation  of 
certain  glands  with  certain  substances. 

•ft.  The  conspicuous  instance  under  this  head  is  the 
fact,  that  one  gland  secretes  one  fluid,  another  a  different 
one  invariably.  Again,  this  relation  explains  the  opera- 
tion of  mercury  on  the  salivary,  and  of  cantharides  on  the 
renal  glands. 

Q.  Will  you  state  some  of  the  peculiar  modes  of  glandu- 
lar sympathies? 

•ft.  There  is  that  of  the  liver  with  the  brain,  the  testi- 
cles with  the  pectoral  organs;  the  disorders  of  the  kidneys 
in  exciting  vomiting,  the  sympathy  of  the  uterus  with  the 
mammae. 

Q.  Give  examples  of  the  different  inflammation  in  dif- 
ferent glands. 

•ft.  The  inflammation  of  the  kidney  differs  from  that  of 
the  liver;  that  of  the  prostate  gland  from  the  testicles. 
There  is  a  difference  in  the  symptoms. 

Q.  You  have  said  that  the  glarfds  have  their  particular 
forms  of  diseases,  specify  this  position. 

•ft.  While  the  liver  is  subject  to  hydatids,  the  salivary 
glands  and  testicle  never  have  them.  Observe  how  much 
more  frequent  sarcocele  is,  than  a  scirrhus  of  the  parotids. 

Q.  What  characters  appertain  to  the  vitality  of  the 
glands? 


GLANDULAR    SYSTEM. 


283 


fc/2.  They  are  the  peculiarity  of  the  life  of  the  glands; 
the  remittent  action  of  glandular  life;  the  whole  of  the 
glandular  system  is  never  increased  in  its  vital  forces  at 
the  same  time;  glandular  vitality  is  influenced  by  climate 
and  season;  sex  has  great  influence  on  the  vitality  of  the 
glands.  These  are  the  remarkable  characters  in  the  vita- 
lity of  the  glands. 

Q.  What  do  you  mean  by  remission  in  the  glandular 
life? 

*#.  It  is  this;  that  although  secretion  is  constantly  going 
on,  yet  it  is  much  more  active  at  some  times  than  at 
others. 

Q.  How  does  season  affect  the  glandular  system? 

«#.  In  the  winter  the  internal  glandular  system  is  active, 
and  the  skin  torpid  ;  while  in  summer  the  skin  is  active  at 
the  expense  of  the  internal  glands. 

Development  of  the  Glandular  System. 

Q.  What  is  the  state  of  the  glands  in  the  foetus? 

•#.  Much  developed,  but  inactive.  There  is  little  need 
for  secretion,  and  no  room  for  excretion  in  the  foetus. 

Q.  What  causes  excite  the  glandular  system  at  birth? 

.#.  The  change  in  their  blood  from  black  to  red;  and 
the  excitement  carried  to  their  excretories  by  air,  food, 
and  other  irritations  at  their  mouths. 

Q.  What  glands  are  most  disordered  in  infancy  ? 

«#.   The  mucous  and  lachrymal  glands. 

Q.  Is  the  glandular  system  most  diseased  in  infant  life 
or  after  growth? 

./?.  It  is  most  diseased  after  growth.  In  infancy  the 
lymphatic  System  is  most  affected,  in  adults  the  glandular. 


284  GLANDULAR    SYSTEM. 

Q.  Mention  some  of  the  glands  which  are  particularly 
active  at  different  periods  of  life? 

<ft.  The  lachrymal  glands  are  most  remarkably  active 
in  infancy;  the  genital  glands  are  so  in  youth;  the  hepatic 
system  is  most  energetic  in  adult  life. 

Q.  How  do  you  account  for  the  activity  of  many  glands 
in  old  age? 

«#.  Decomposition  requires  many  things  to  be  cast  off 
by  the  excretories ;  the  functions  of  the  skin  ceasing,  a  de- 
termination takes  place  to  the  glands  of  the  abdomen. 

Q.  Is  the  communication  between  the  arteries  and  ex- 
cretory ducts  of  a  gland  direct,  or  is  there  an  intermediate 
substance? 

A.  In  the  liver,  testicles,  and  kidneys,  there  is  this  evi- 
dent, direct  communication;  but  in  others  it  is  not  demon- 
strable. 


PATHOLOGY  OF  THE  GLANDULAR  SYSTEM. 

Q.  What  are  the  diseases  of  this  texture? 

A.  Each  gland  has  its  own  diseases.  The  glands  differ 
in  structure,  are  without  common  properties,  and  there- 
fore in  detailing  diseases  of  the  glands,  each  organ  is  to  be 
separately  mentioned. 

Q.  There  are^  some  affections  in  common  with  all 
glands. 

A.   These  are  enlargement  and  diminution  of  size. 

Q.   Inflammation  has  a  common  effect  on  all  the  glands. 

A.  It  alters  the  secretions  of  all;  it  checks  altogether 
the  secretory  action  in  many. 

• 


GLANDULAR    SYSTEM.  285 

Q.  What  are  the  diseases  of  the  lachrymal  gland? 

A.  It  is  so  little  liable  to  disease,  as  to  require  no  con- 
sideration here. 

Q.  Enumerate  the  salivary  glands  ? 

*ft.  They  are  the  parotid,  the  maxillary,  and  the  sub- 
lingual. 

Q.  What  are  the  diseases  of  the  parotid  glands? 

•fl.  Indisposed  to  suppurate,  they  inflame,  enlarge,  and 
resolve.  They  are  the  seat  of  mumps — they  become 
scirrhous. 

Q.  Is  it  the  substance  of  the  gland  or  the  surrounding 
tissue  that  enlarges  so  much  in  these  cases? 

«/2.  It  is  doubtless  ascribable  to  both;  but  the  surround- 
ing texture  is  materially  concerned  in  it. 

Q.  What  is  the  most  frequent  disease  of  the  liver? 

A.   Inflammation,  acute  and  chronic. 

Q.  Are  the  membranes  and  substance  of  the  liver 
usually  inflamed  at  the  same  time? 

Jl.  Not  usually;  the  texture  of  the  two  varies. 

Q.  When  does  singultus  appear  in  hepatitis? 

Ji.  When  the  convex  surface  is  inflamed,  the  diaphragm 
is  so  irritated  as  to  occasion  hiccup.  Cough  ia  likewise 
more  frequent  in  this  case. 

Q.  What  symptoms  are  specially  connected  with  in- 
flammation of  the  concave  surface  of  the  liver? 

JL.  Vomiting. 

Q.  How  does  hepatitis  terminate  ? 

A.  By  resolution  and  suppuration. 

Q.  What  are  the  products  of  chronic  hepatitis  ? 

J3.  Great  enlargement  of  the  liver,  and  again  the  op- 
posite state  of  diminished  volume 


286  GLANDULAR    SYSTEM. 

Q.  There  are  other  hepatic  disorganizations? 

*#.  Steatomatous  tumours,  tubercles,  fatty  depositions, 
hydatids,  &c.  It  is  not  necessary  particularly  to  notice 
jaundice,  as  it  arises  in  common  from  the  liver  and  gall- 
bladder. There  are  numerous  symptomatic  diseases  of  the 
liver. 

Q.  With  what  affections  is  inflammation  of  the  kidney 
confounded  ? 

«#.  With  lumbago  and  phlegmon  in  the  region  of  the 
kidney. 

Q.  What  are  the  principal  diagnostics? 

«#.  The  pain  of  nephritis  is  increased  by  pressure;  and 
in  nephritis  the  conditions  of  the  urine  are  much  al- 
tered. 

Q.  Name  some  other  morbid  states  of  the  kidney. 

*fl.   There  is  flaccidity  of  the  organ  and  hydatids. 

Q.  At  what  period  of  life  does  the  prostate  gland  as- 
sume disease? 

&.  Not  usually  before  puberty. 

Q.  What  are  the  diseases  of  the  prostate? 

*#.  Inflammation,  induration,  varices,  cancer. 

Q.  How  do  you,  in  diseases  of  the  testicle,  distinguish 
sarcocele  from  hydrocele? 

Ji.  The  sarcocele  is  harder  than  hydrocele.  This  is  one 
way  to  distinguish  them. 

Q.  Are  the  testicles  equally  liable  at  all  times  of  life  to 
disease? 

A.  Like  the  prostate  gland,  they  are  seldom  diseased 
before  puberty. 

Q.  What  are  the  principal  diseases  of  the  mammary 
gland? 


GLANDULAR    SYSTEM. 


287 


<fl.  Inflammation,  ending  in  abscess  during  lactation — 
and  cancer,  chiefly  at  advanced  periods  of  life. 

Q.  What  have  you  to  say  of  diseases  of  the  spleen? 

•#.  That  inflammation  of  that  gland  is  very  rare;  sup- 
puration is  still  more  so.  Intermittents  chiefly  induce  dis- 
ease of  the  spleen.  It  is  liable  to  cartilaginous  and  osseous 
indurations. 

Q.  What  is  the  disease  of  the  thyroid  gland? 

*#.  Goitre. 


(    288    ) 


DERMOID  SYSTEM. 

Q.  What  are  the  uses  of  this  texture? 

*#.  To  defend  parts  from  external  injury;  to  eliminate 
much  of  the  residue  of  nutrition  and  digestion;  and  to 
throw  it  into  relation  with  external  bodies.  It  connects 
the  existence  of  man  with  surrounding  objects. 

Forms  of  the  Dermoid  System. 

Q.  There  are  several  kinds  of  wrinkles  on  the  skin,  to 
what  are  they  owing? 

•ft.  To  the  subjacent  muscles,  to  the  motions  of  parts, 
and  to  old  age.  In  this  last  the  wrinkles  are  owing  to 
the  removal  of  sub-cutaneous  fat. 

Q.  If  the  sub-cutaneous  fat  be  removed  by  emaciation 
in  young  persons,  do  you  perceive  wrinkles  in  the  skin? 

Ji.  No;  because  the  organic  contractility  is  not  lost,  as 
in  old  age,  and  the  skin  adapts  itself  to  the  emaciated 
parts. 

Q.  How  does  the  connexion  of  the  skin  with  the  sub- 
jacent parts  in  man,  differ  from  that  connexion  in  ani- 
mals? 

Jl.  In  animals  the  skin  lies  over  a  fleshy  layer  called 
panniculus,  which  the  animal  moves  at  pleasure.  In  man 
the  only  resemblance  to  this  is  the  occipito-frontalis  and 
the  platisma  myoides  muscles. 


BERM01D    SYSTEM. 

Organization  of  the  Dermoid  System. 
I.   Texture  peculiar  to  the  Organization. 

Q.  What  does  the  dermoid  texture  comprise? 

«#.  The  chorion,  the  reticular  body,  and  the  papillae. 

a.    Of  the  Chorion. 

Q.  On  what  parts  is  the  chorion  thickest? 

«/?.  On  the  sole  of  the  foot,  the  palm  of  the  hand,  the 
scalp,  and  on  the  back.  It  is  thinnest  on  the  female  breast, 
on  the  penis  and  scrotum. 

Q.  In  which  sex  is  it  thinnest? 

«#.   In  females. 

Q.  What  modifications  does  the  dermoid  chorion  exhi- 
bit on  its  internal  face? 

.#.  On  the  sole  of  the  foot  and  palm  of  the  hand  it  is 
firmly  connected  with  the  cellular  substance  by  strong 
and  numerous  fibres.  This  fibrous  connexion  is  important 
to  the  functions  of  the  parts. 

Q.  What  are  the  peculiarities  of  the  internal  face  of  the 
chorion  on  other  parts  of  the  body? 

t#.  On  the  internal  face  over  the  body  there  are  but 
few  fibres,  and  the  skin  hangs  loosely;  between  the  fibres 
are  spaces  filled  with  small  fatty  parcels.  On  the  back  of 
the  hand  and  foot,  on  the  scalp,  and  where  the  beard 
grows,  there  are  openings  only  for  the  hairs  to  go  through, 
the  surface  being  white  and  smooth. 

Q.  What  effect  has  long  maceration  on  the  chorion? 

«#.  It  shows  that  the  chorion  on  the  external  face  is 
37 


^ 


290  PERMOID    SYSTEM. 


actually  perforated  by  foramina  for  the  passage  of  the 
hairs,  the  nerves,  blood-vessels,  exhalents,  absorbents,  &c. 

Q.   What  texture  does  the  chorion  most  resemble? 

«#.  In  its  appearance  in  certain  parts,  in  its  serving  for 
the  insertion  of  muscles,  in  its  melting  gradually  into  gela- 
tine, and  in  some  other  respects,  it  resembles  the  fibrous 
tissue. 

Q.  On  which  surface  of  the  chorion  do  eruptive  diseases 
form? 

«#.  On  the  external  altogether.  Phlegmon  forms  in  the 
cellular  substance  beneath  the  chorion;  the  small-pox, 
erysipelas,  &c.  are  found  on  the  exterior  face. 

Q.  What  then  are  the  functions  of  the  chorion  ? 

t/?.  Being  intended  neither  for  sensation  nor  circulation, 
it  serves  to  protect  and  defend  the  body. 

b.    Of  the  Reticular  Texture. 

Q.  What  do  you  understand  by  this? 

*fl.  It  is  a  capillary  net-work  of  vessels  on  the  exterior 
of  the  chorion,  forming  with  the  papillae  a  layer  between 
the  chorion  and  epidermis. 

Q.  What  fluids  are  contained  in  this  reticular  texture? 

*#.  Those  which  give  the  colour  or  teint  to  the  indivi- 
dual. 

Q.  What  proves  that  this  teint  is  foreign  to  the  chorion 
and  epidermis? 

«/?.  These  two  having  the  same  colour  in  whites  and 
blacks. 

Q.  Is  the  reticular  texture  ever  renewed  after  once  be- 
ing destroyed? 

•#.   It  is  not;  cicatrices  are  white  in  all  persons. 


DERMOTD    SYSTEM,  291 

Q.  Is  there  not  another  set  of  capillaries  in  the  reticu- 
lar  body  besides  that  which  contains  the  colouring  princi- 
ple? 

<fl.  Yes;  there  are  thos^  which  furnish  the  exhalents  of 
the  perspiration. 

Q.  Why  is  this  last  portion  of  the  reticular  body  so  im- 
portant to  pathologists? 

«tf.  Because  it  is  the  seat  of  the  eruptive  diseases,  erysi- 
pelas, &c. 

Q.  What  is  the  reason  that  in  serous  effusions  on  the 
serous  membranes,  bladders  of  that  fluid  do  not  form,  as 
on  the  skin? 

JL.  Because  on  these  membranes  there  is  no  epidermis 
to  form  the  blister. 

Q.  What'part  of  this  reticular  capillary  system  is  most 
apt  to  be  filled  with  blood? 

«#.   The  facial  portion. 

Q.  What'  is  the  reason  of  this? 

«#.  Because  in  the  face  the  communication  between  the 
reticular  texture  and  the  arteries  of  the  chorion  is  more 
free,  and  because  the  sensibility  of  the  texture  in  the  face 
is  greater  than  it  is  elsewhere  in  that  tissue. 

Q.  In  what  three  modes^does  the  face  express  the  pas- 
sions? 

»#.  In  the  eye,  in  the  muscles  of  the  face,  and  in  the 
facial  reticular  texture.  This  last  is  entirely  involuntary. 

Q.  Can  you  say  how  this  reticular  tissue  expresses  the 
passions?  jp 

«#.  By  the  quantity  of  blood,  as  in  blushing  under 
mental  emotion,  and  by  the  absence  of  blood,  as  in  the 
paleness  of  fear. 

Q.  What   pathological   fact   arises    from    this   natural 


DERMOID    SYSTEM, 

susceptibility  to  increased  sanguineous  fulness  in  the 
face? 

«#.  That  in  cutaneous  diseases,  especially  variola,  the 
face  is  most  violently  affected.  The  affections  of  this  re- 
ticular  tissue  of  the  face  are  indicative  in  many  cases  of 
internal  visceral  disease. 

Q.  Repeat  the  two  anatomical  divisions  of  the  reticular 
capillary  system. 

t#.  That  which  contains  the  colouring  teint,  and  that 
which  affords  the  fluids  of  transpiration. 

c.   Of  the  Papillse. 

Q.  What  do  you  mean  by  these? 

Jl.  They  are  small  eminences  arising  from  the  external 
chorion,  which  pierce  the  reticular  surface,  and  become 
contiguous  to  the  epidermis. 

Q.  What  are  apt  to  be  confounded  with  these  papillae? 

<ft.  Certain  cellular,  vascular,  or  nervous  bunches,  or 
sebaceous  glands,  which  are  lodged  in  the  small  oblique 
canals,  terminated  by  the  openings  of  the  chorion  under 
the  epidermis.  These  bunches  or  bundles,  or  eminences, 
are  observable  on  the  outside  of  the  arms,  and  on  the 
back. 

Q.  What  occasions  the  petechiae  of  adynamic  fevers  ? 

t#.  Extravasation  of  blood  in  the  cellular  texture  of  the 
small  pores,  which  open  on  the  exterior  of  the  chorion, 
to  transmit  the  hair$  &c.  This  occasions  these  petechiae. 

Q.  What  is  the  structure  of  the  papillae? 

«#.  Analogy  supposes  them  to  be  nervous  terminations, 
but  this  analogy  has  not  been  sustained  as  yet  by  demon- 
stration. 


DERMOTD    SYSTEM.  293 


Action  of  Different  Bodies  on  the  Dermoid  Texture, 

Q.  What  effect  has  light  on  the  dermoid  texture? 
A.   It  whitens  it,  and  this  independently  of  heat.     A 
proof  of  this  is,  that  clothing  which  does  not  exclude  the 
influence  of  heat  from  the  skin,  prevents  the  blanching  of 
the  skin  which  light  occasions. 

Q.  What  are  the  effects  of  heat  on  the  dermoid  tissue  ? 
*#.  The  first  effect  is  to  expand  the  texture  and  increase 
the  flow  of  fluids  to  and  through  it.  In  a  higher  degree, 
heat  produces  redness,  a  kind  of  erysipelas.  Applied  more 
powerfully,  it  reddens  and  vesicates  the  skin.  In  greater 
intensity  it  produces  the  horny  hardening,  and  lastly,  it  is 
blackened  and  reduced  to  carbon. 

Q.  In  the  production  of  redness  and  vesication,  on 
what  does  heat  act? 

«#.  On  the  vital  forces  of  the  part;  but  the  subsequent 
steps  are  on  the  textural  properties,  and  take  place  alike 
in  the  dead  and  living  skin. 

Q.  Does  the  skin  preserve  an  equality  of  texture? 
«/?.  It  does.  It  prevents  the  effects  of  a  greatly  in- 
creased heat,  refusing  admission  to  the  caloric;  while  in 
very  cold  countries,  it  prevents  the  rapid  escape  of  animal 
internal  heat.  It  is  a  curious  fact,  that  internal  organs  ex- 
posed to  the  air  do  not  thus  resist  the  changes  of  tempera- 
ture. 

Q.   How  does  cold  affect  the  dermoid  texture? 
«#.   Variously,  according  to  the  degree  at  which  it  is 
applied.     First  it  contracts  the  vessels  so  that  the  usually 
passing  fluids  cannot  escape;  the  next  degree  produces 
dermoid  redness;  and  lastly,  it  brings  on  gangrene. 


294  DERMOID    SYSTEM. 

Q.   There  are  two  phenomena  in  gangrene  carefully  to 
be  distinguished,  what  are  they? 

«#.  The  mortification  of  the  part,  and  the  putrefaction 
of  the  mortified  part. 

Q.  What  hastens  the  putrefaction  of  the  mortified  part? 

*#.  The  process  is  rapid  in  proportion  to  the  quantity 
of  blood  it  contains. 

Q.  Then  antisceptic  is  a  relative  term,  to  be  under- 
stood in  a  double  sense? 

t/2.  It  is;  for  it  may  prevent  the  mortification  of  a 
part,  and  also  the  putrefaction  of  a  part  already  mortified. 
How  different  are  these  two  objects. 

Q.  In  what  distinctive  sense  are  the  exhalation  and 
solution  of  transpired  fluids  to  be  understood? 

»/?.  In  this,  that  the  exhalation  of  the  perspiration  is  a 
vital  phenomenon ;  its  solution  in  the  air  is  physical.  They 
are  totally  independent  of  each  other. 

Q.  Sweating,  then,  is  owing  to  two  causes  wholly  in- 
dependent of  each  other,  what  are  they  ? 

*fl.  The  one  is  the  increase  of  exhalation,  the  other  is  a 
diminished  solution  by  the  air  of  what  is  exhaled. 

Q.  What  are  the  several  causes  which  increase  exhala- 
tion by  the  skin? 

«/?.  Whatever  increases  the  determination  of  fluids  to 
the  surface,  as  severe  exercise,  fever,  &c.  are  one  set  of 
causes.  The  exhaled  fluid  is  increased  by  external  causes, 
which  relax  and  expand  the  cutaneous  organ,  as  the  heat 
of  summer,  warm  bathing,  &c.  The  action  of  the  skin  is 
sympathetically  increased  in  diseases;  you  see  this  in  the 
sweats  of  phthisis.  The  passions,  by  acting  on  the  epi- 
gastric organs,  increase  sweating  by  sympathy. 

Q.  What  effect  has  bathing  in  water  on  the  skin? 


DERMOID    SYSTEM. 

Jl.  It  cleanses  it  from  saline  and  oily  matter.  It  may, 
in  certain  cases,  increase  or  diminish  the  vital  forces  of  the 
skin,  but  it  does  not  alter  its  texture. 

Q.  At  what  season  is  bathing  most  useful? 

t/?.  In  summer,  when  exhalation  is  greatest  and  most 
compound. 

2.  Paris  common  to  the.  Organization  of  the  Dermoid 
System. 

Q.  Does  cellular  texture  abound  in  the  chorion  ? 

«#.  It  does,  in  great  abundance.  The  chorion  may  be 
considered  as  a  sponge,  the  interstices  of  which  are  filled 
with  cellular  texture.  When  the  chorion  has  lost  its  cel- 
lular texture  it  is  like  a  sieve. 

Q.  Do  acute  diseases  affect  the  texture  of  the  chorion  ? 

•fl.  They  do  not;  they  attack  its  cellular  tissue.  The 
chorion  is  disorganized  in  elephantiasis. 

Q.  Does  the  cellular  texture  of  the  chorion  extend  to 
i£s  external  surface  beneath  the  epidermis? 

J2.  The  fact  that  granulations  do  not  arise  when  the 
epidermis  is  destroyed  would  induce  the  belief  that  there 
is  no  cellular  substance  on  the  external  surface  of  the 
chorion;  because,  wherever  there  is  cellular  substance, 
there  you  will  see  granulations,  when  the  cellular  texture 
is  laid  bare. 

Q.  There  are  two  sets  of  absorbents  on  the  chorion, 
name  them. 

•ft.  Those  which  arise  from  the  chorion  and  return  its 
materials  to  the  blood,  and  those  which  absorb  foreign 
substances  through  the  epidermis. 


296  DERMOID    SYSTEM. 

Q.  Do  you  not  beg  the  question,  in  asserting  the  ex- 
istence of  cutaneous  absorption,  as  the  term  is  ordinarily 
accepted  ? 

«#.  The  following  considerations  establish  its  existence. 
The  sub-cutaneous  absorbents  are  vastly  too  numerous  in 
proportion,  to  carry  back  the  fat  and  serum  of  the  parts; 
they  must  therefore  have  other  offices.  Mercury,  can- 
tharides,  emetics,  and  purgatives,  are  evidently  absorbed. 
Bichat,  while  in  a  dissecting  room,  breathed  through  a 
tube  communicating  with  the  external  air,  yet  his  breath 
was  as  fetid  as  if  he  had  inhaled  it  by  breathing  the  air  of 
the  room.  This  proves  that  there  is  some  other  route  for 
the  vapour  of  the  dissecting  room,  than  by  the  lungs;  this 
is  the  skin. 

Q.  What  reason  is  there  for  denying  the  nervous  trans- 
mission of  these  metallic  and  other  odours  and  vapours? 

«#.  The  fact  that  in  certain  punctures  the  whole  course 
of  the  absorbents  and  glands  is  affected ;  and  particularly 
that  by  frictions,  and  transfusions  into  the  veins  of  the 
same  substances  used  in  frictions,  similar  effects  are  pro- 
duced. 

Q.  How  do  you  account  for  the  experiments  which  dis- 
prove cutaneous  absorption? 

4#.  They  are  explained  by  the  ever-varying  sensibility 
of  the  skin.  This  is  witnessed  every  day  in  the  reception 
or  rejection  of  contagions,  such  as  the  vaccine  and  small- 
pox. 

Q.  What  persons  and  circumstances  are  most  favour- 
able to  cutaneous  absorption? 

t/?.  Children  and  women  are  the  persons  most  suscep- 
tible of  contagions;  and,  as  during  sleep  and  hunger  the 


DERMOID    SYSTEM.  297 

vital  forces  are  feeblest,  it  is  under  those  circumstances 
that  the  skin  is  most  susceptible  of  the  action  of  these 
poisons. 

Q.  How  are  the  cutaneous  absorptions  from  which  dis- 
eases arise  to  be  divided  ? 

Jl.  Into  those  which  act  through  the  cuticle,  as  the 
itch,  herpes,  tinea,  and  the  pestilential  diseases;  and  into 
those  which  require  the  removal  of  the  cuticle,  as  the  vac- 
cine, variola,  hydrophobia,  the  bite  of  the  viper. 

Q.  Where  do  the  cutaneous  exhalents  arise? 

A.  From  the  external  capillary  system  which  surrounds 
the  chorion  and  embraces  the  papillae. 

Q.  What  proves  the  existence  of  exhalents  ? 

«/?.  It  is  proved  by  the  injections  which  are  poured  out 
on  the  skin,  and  the  sanguineous  exhalation  in  the  form 
of  bloody  sweating. 

Q.  To  what  cause  are  many  winter  coughs  to  be  as- 
cribed ? 

«#.  To  irritating  matters,  which  in  pulmonary  transpi- 
ration are  lodged  in  the  lungs;  and  this  accounts  for  coughs 
which  are  irritating  without  increased  mucous  effusion. 

Q.  Where  are  the  cutaneous  exhalents  most  abundant? 

<fl.  In  the  face  and  chest,  where  sweating  is  most  pro- 
fuse. 

Q.  What  effect  has  season  on  cutaneous  transpiration  ? 

«#.  It  is  most  abundant  in  summer.  In  winter  the  pul- 
monary exhalation  and  urinary  secretion  act  vicariously. 

Q.  Whence  is  the  source  of  the  oily  fluid  which  is 
thrown  out  on  the  skin? 

t/?.   It  is  an  oily  exhalation,  such  as  that  of  fat  which 
takes  place  in  the  cellular  tissue.     Bichat  has  never  been 
able  to  discover  sebaceous  glands. 
38 


298  UERMOID    SYSTEM. 

Q.  What  is  the  office  of  this  oily  fluid? 

•/#.  It  serves  to  soften  the  skin  so  as  to  prevent  its 
cracking. 

Q.  Why  not  consider  this  oil  as  an  exudation  of  fat 
through  the  skin? 

«/?.  Because,  in  several  parts  where  there  is  the  least  fat, 
there  is  the  most  oil,  and  vice  versa.  Besides,  physical 
transudation  is  denied  on  vital  principles. 

Properties  of  the  Dermoid  System. 

1.  Properties  of  Texture. 

Q.  What  properties  of  texture  are  found  in  the  dermoid 
tissue? 

*tf.  Extensibility  and  contractility  to  great  extent.  See 
this  in  dropsies,  in  pregnancy,  in  tumours.  Observe  how 
the  skin  retracts  in  a  wound.  You  will  find  that  these  pro- 
perties of  texture  are  manifested  in  dead  bodies.  They 
are  not  dependent  on  vital  forces,  but  derive  an  increase 
of  energy  from  them.  • 

Q.  When  the  extension  of  the  gkin  is  increased,  what 
takes  place  in  the  fibres  of  the  dermis,  and  in  the*  spaces 
between  them  ? 

*#.   The  fibres  are  separated,  and  the  spaces  increase. 

Q.  How  is  the  contraction  of  the  dermoid  texture  from 
cold  explained? 

«/?.  The  fibres  and  spaces  are  much  diminished  on  the 
inner  surface  of  the  chorion;  but  as  the  external  face  of 
the  chorion  does  not  contract  in  the  same  degree,  a  rough- 
ness is  occasioned. 


DERMOID    SYSTEM.  299 

Q.  In  cases  of  dermoid  extension,  is  the  chorion  ren- 
dered thinner? 

Jl.  It  is  in  almost  every  case. 

2.    Vital  Properties. 

Q.  What  property  of  animal  life  is  most  conspicuous 
in  the  $ikin? 

e/2.  Above  all  others,  animal  sensibility. 

Q.  What  functions  does  this  property  govern? 

«#.  Those  of  feeling  and  of  touch. 

Q.  In  what  does  feeling  differ  from  touch? 

t#.  Feeling  perceives  the  impression  and  general  mo- 
difications of  surrounding  bodies;  touch  ascertains  the  spe- 
cial modifications  of  those  bodies,  as  to  form,  dimensions, 
&c. 

Q.  In  what  does  touch  differ  from  other  senses? 

«#.  Touch  requires  no  peculiar  modification  of  sensi- 
bility; the  eye,  the  ear,  the  organ  of  smelling,  all  require 
this  peculiarity  of  sensibility.  The  touch  is  exercised  on 
the  qualities  of  bodies  emphatically  tangible,  and  not  on 
their  colour,  flavour,  and  such  like  qualities.  The  touch  is 
exercised  from  voluntary  impulse;  it  is  not  so  with  the 
other  senses.  Touch  is  an  operation  somewhat  consequen- 
tial to  the  action  ofHhe  other  senses.  All  the  other  senses 
require  not  only  peculiar  sensibility,  but  a  peculiarity  of 
structure;  whereas  accurate  touch  only  requires  form  con- 
venient for  exposing  surfaces  of  contact;  such  form  is  seen 
in  the  hand  of  man. 

Q.  What  part  of  the  dermoid  texture  belongs  to  animal 
life,  and  what  to  organic  life? 

,*#.  The  papillae  are   governed  by  animal  sensibility. 


300  DERMOID    SYSTEM. 

The  reticular  body  belongs  to  organic  life.     The  chorion 
is  passive. 

Q.  When  the  animal  sensibility  of  the  papilla?  is  ex- 
alted in  disease,  what  peculiar  symptoms  are  presented? 

«#  A  smarting,  burning  pain,  known  only  to  the  pa- 
pillae; such  is  the  case  with  blisters,  erysipelas.  You  have 
itching,  which  is  a  sensation  also  peculiar  to  the  papillae, 
as  well  as  the  curious  sensation  from  tickling.  ISlpne  of 
these  sensations  are  known  on  the  mucous,  serous  or  other 
tissues. 

Q.  Is  there  any  other  particular  of  the  papillary  animal 
sensibility  worthy  of  notice? 

*#.  That  it  is  much  regulated  by  habit,  as  you  see  in 
the  exposure  of  the  skin  in  some  nations;  the  nakedness 
of  some,  and  the  full  dress  of  others. 

Q.  What  destroys  feeling? 

*ft.   Inflammation,  paralysis,  and  other  morbid  states. 

Q.  When  animal  sensibility  is  in  exercise,  is  there  an 
erection  of  the  papillae? 

*ft.   Observation  would  answer  in  the  negative. 

Q.   Does  animal  contractility  exist  in  this  texture? 

J2.   It  does  not. 

Q.  What  functions  presuppose  the  activity  of  organic 
sensibility  and  of  insensible  organic  contractility  in  this 
texture  ?  * 

t/#.  Exhalation,  absorption,  the  exhalation  of  the  oily 
matter,  the  capillary  circulation,  and  the  nutrition  of  the 
whole  dermoid  texture;  and  lastly,  the  excitement  from 
external  bodies. 

Q.   How  are  the  diseases  of  the  skin  to  be  divided? 

*#.  Into  those  of  the  papillae  in  which  animal  sensibility 
is  exalted  or  diminished;  the  firstvin  certain  acute  sensibi- 


DERM01D    SYSTEM.  301 

lities,  the  second  in  paralysis.  .Next,  there  are  the  diseases 
of  the  cellular  texture  of  the  chorion,  as  the  inflammation 
of  that  texturfe  over  a  bile  or  phlegmon.  Then  there  are 
diseases  of  the  external  capillary  net-work,  as  erysipelas, 
herpes,  measles,  scarlatina.  The  chorion,  lastly,  is  subject 
only  to  chronic  affections,  as  elephantiasis. 

Q.  What  important  inference  is  to  be  deduced  from 
this  division  of  the  diseases  of  the  skin? 

«#.  That  all  those  diseases,  except  those  in  which  ani- 
mal sensibility  is  exalted  or  diminished,  proceed  from  an 
alteration  of  the  organic  sensibility  and  insensible  organic 
contractility  of  the  parts.  And  it  is  from  these  alterations 
that  numerous  phenomena  are  to  be  accounted  for,  as  the 
failure  of  blisters  to  draw  from  too  much  or  too  little  ex- 
citement, in  the  greater  or  less  sweating  at  different  times. 

Q.  Will  you  enumerate  some  remarkable  passive  sym- 
pathies of  the  dermoid  telkture? 

«/#.  One  very  striking  one  is  the  sensation  of  cold  pro- 
duced by  disorder  of  the  internal  organs;  these  affect  the 
animal  sensibility  of  the  skin.  Flushes  of  heat  are  also 
from  this  cause.  Digestion,  the  emission  of  semen,  the 
diseases  of  the  serous  and  mucous  systems,  all  produce 
chilliness. 

Q.  The  sensations,  then,  of  heat  and  cold,  arise  from 
various  causes? 

*#.  Yes.  They  arise  from  an  increase  or  diminution  of 
atmospheric  temperature;  from  preternatural  development 
in  some  diseases,  as  of  heat  in  phlegmon;  there  is  a  dimi- 
nution of  heat  in  other  cases,  as  where  an  artery  is  tied. 
Caloric  Ss  disengaged  sometimes,  generally  or  locally, 
without  inflammation;  lastly,  there  are  sympathetic  sensa- 
tions of  heat  and  cold. 


;. 


302  DERMOID    SYSTEM 

Q.  Are  the  organic  vital  properties  of  the  dermoid  tex- 
ture sympathetically  affected? 

«/?.  They  are;  as  when  cold  drinks  check,  or  warm 
fluids  taken  into  the  stomach,  increase  perspiration. 

Q.  Whence  the  most  usual  excitant  of  these  passive 
cutaneous  sympathies? 

Jl.  They  most  frequently  arise  from  the  mucous  mem- 
branes of  the  stomach;  but  they  often  proceed  likewise 
from  the  lungs. 

Q.  What  are  the  active  sympathies  of  the  papillae? 

*#.  When  vpmiting  or  syncope  follow,  tickling,  you 
have  an  example  of  an  active  cutaneous  sympathy. 

Q.  How  do  the  organic  forces  of  the  dermoid  texture 
excite  active  sympathies? 

.#.  These  sympathies  are  produced  not  by  translation 
of  morbific  matter,  nor  by  the  repercussion  of  fluids,  but 
by  exciting  the  predominant  vital  forces  of  the  sympa- 
thizing organs. 

Q.   Give  an  example  of  this. 

«#.  In  inflammation  of  the  thoracic  serous  membrane, 
the  perspiration  is  checked  by  cold.  What  does  this  mean, 
but  that  the  organic  vital  forces  of  the  external  capillary 
tissue  of  the  skin  are  altered;  a  sympathetic  impression  is 
made  on  the  organic  forces  of  the  exhalents  of  the  pleura; 
these  last,  which  only  admit  serum  in  health,  are  placed 
in  relation  to  blood,  and  inflammation  takes  place. 

Q.  At  what  season  of  the  year  are  the  organic  forces  of 
the  dermoid  texture  most  exalted? 

•ft..  In  the  hot  seasons;  hence  the  active  sympathies  are 
then  most  prevalent,  and  most  to  be  dreaded. 

Q.  How  is  it  that  the  active  cutaneous  sympathies  vary 
in  different  persons? 


DERMOID    SYSTEM.  303 

«/?.  Because  of  the  great  difference,  in  various  persons, 
in  predisposition  to  disease.  In  one,  a  cutaneous  sympa- 
thy excites  the  predominant  forces  of  a  serous,  and  in 
another  of  a  mucous  tissue. 

Q.  Why  is  it  that  the  sympathies  of  animal  contracti- 
lity, and  of  sensible  organic  contractility  in  the  skin  are 
not  active? 

•d.  Because  the  dermoid  texture  has  not  these  proper- 
ties. 

Q.  What  are  the  important  characters  of  dermoid  life 
and  vital  forces? 

«#.  Animal  sensibility  is  more  acute  in  some  parts  than 
others;  it  is  more  acute  in  the  palms  of  the  hands  and 
soles  of  the  feet,  and  in  the  hypochondriac  regions.  Or- 
ganic sensibility  varies  in  force  in  different  parts. 

Q.  There  is  an  important  difference  between  the  ani- 
mal and  organic  forces  of  the  dermoid  texture,  what  is  it? 

«/?.  The  animal  vital  forces  of  the  skin  are  intermit- 
tent in  action,  the  organic  forces  are  continually  opera- 
tive. During  sleep,  these  organic  forces  are  said  to  be 
increased  in  activity; 

Q.  What  arises  from  this  increased  activity  of  the  or- 
ganic vital  forces  of  the  skin  during  sleep? 

Ji.  Hence  it  is  that  those  diseases  have  their  exacerba- 
tions at  night,  which  affect  mostly  the  organic  forces; 
whereas  those  that  affect  the  animal  vital  forces  of  the 
skin,  are  not  thus  exacerbated  at  night. 

Q.  What  effect  has  sex  on  the  cutaneous  vital  forces? 

*#.  The  animal  vital  forces  of  the  skin  are  more  acute 
in.  the  female  than  in  the  male  sex. 


304  DERMOTD    SYSTEM. 


Development  of  the  Dermoid  System, 

Q.  At  what  period  of  life  does  most  blood  enter  the  skin  ? 

.#.  In  the  foetal  period.  In  advanced  life  there  is  least 
blood  in  the  dermoid  texture. 

„,(?.  What  evidence  is  there  that  the  organic  vital  forces 
of  the  skin  in  the  foetus  are  active? 

«#.  The  formation  of  the  unctuous  viscid  fluid  which  is 
seen  on  the  foetal  skin.  Perhaps  the  liquor  amnii  is  form- 
ed and  absorbed  by  the  foetal  skin. 

Q.  What  do  you  infer  from  the  foetal  skin  remaining 
livid  some  time  after  birth  ? 

t/#.  That  the  pulmonary  function  is  not  free. 

Q.  At  what  period  of  life  is  there  least  sweating? 

*ft.   During  childhood  and  infancy. 

Q.  Why  does  the  skin  radiate  active  sympathies  more 
freely  when  it  is  sweating  than  when  dry? 

.#.  Because,  while  perspiring,  its  organic  vital  forces 
are  most  active;  and  hence  these  sympathies. 

Q.  What  substance  predominates  in  the  skin  of  child- 
hood and  of  age? 

«#.  In  early  life, , gelatine  predominates;  and  in  age,  a 
fibrous  substance. 

Q.  Why  is  the  skin  a  more  frequent  source  of  disease 
than  other  textures? 

*#.  Because,  from  its  exposed  situation,  it  is  liable  to 
so  many  variations  of  its  vital  forces. 

Q.  Why  is  it  that  touch  is  more  actively  employed  in 
infancy  and  childhood  than  in  old  age? 

•/?.  Because  every  thing  is  novel  to  the  young,  and 
known  to  the  aged. 


SYSTEM. 


305 


Q.  Whence  the  oily  matter  on  the  skin,  according  to 
Beclard  ? 

J2.  He  supposes  it  to  be  secreted  by  the  sebaceous 
glands,  which  resemble  in  structure  the  mucous  glands. 

Q.  What  are  the  striae  so  often  seen  on  the  abdomens 
of  women  who  have  borne  children  ? 

•#.  Cicatrices  in  the  skin,  the  consequences  of  excessive 
distention. 

Q.  What  texture  gives  rise  to  warts? 

.#.  The  dermis. 

Q.  What  are  the  different  sources  of  horny,  cutaneous 
elevations  ? 

«#.  They  arise  sometimes  from  the  cicatrices  of  wounds; 
again,  from  the  sebaceous  follicles ;  and  lastly,  from  the 
horny  layer  of  the  skin. 

Q.  Whence  the  wens,  the  atheromas,  the  steatomas,  and 
melicerous  tumours? 

v2.  They  are  morbid  enlargements  of  the  sebaceous  fol- 
licles. 

Q.  In  what  part  of  the  dermoid  texture  is  tinea  seated? 

t/?.  In  the  sebaceous  follicles. 

Q.  Where  are  the  naevi  materni  seated? 

A.  In  the  vascular  net-work,  the  reticular  texture. 


PATHOLOGY  OF  THE  DERMOID  TEXTURE. 

Q.  How  are  the  diseases  of  the  skin  to  be  divided? 
«#.   Into  the  idiopathic  and  symptomatic. 
Q.  What  is  the  seat  of  the  symptomatic  cutaneous  dis- 
eases? 

39 


306 


DERMOID    SYSTEM. 


•/#.  They  are  seated  in  the  capillaries  of  the  reticular 
and  teguments  external  to  the  chorion. 

Q.  How  are  the  cutaneous  textures  affected  by  dis- 
tention  ? 

v#.  In  great  distention,  the  fibres  of  the  chorion  are 
torn  and  separated;  folds  and  wrinkles  also  arise  from  this 
cause. 

Q.   What  effect  has  chronic  disease  on  the  skin? 

Ji.  It  deranges  the  dermoid  texture,  rendering  it  rough 
and  sallow. 

Q.  What  division  of  the  causes  of  erysipelas  do  you 
make? 

•#.  They  are  external  and  internal,  or  extrinsic  and 
constitutional. 

Q.  Where  is  erythema  or  erysipelas  seated? 

«/2.   In  the  reticular  texture;  the  chorion  is  unaffected. 

Q.   Is  the  chorion  always  sound  in  erysipelas? 

*#.  In  some  cases  the  intense  phlogosis  affects  that  part 
of  the  skin,  and  even  the  subjacent  cellular  texture;  and 
in  these  cases  there  is  phlegmon,  with  great  erysipelatous 
tension. 

Q.  What  is  the  nature  of  the  pain  in  erysipelas? 

Ji.   It  is  an  acute  but  burning  pain. 

Q.  Where  is  erysipelas  most  violent  and  dangerous? 

./?.   On  the  head  and  face. 

Q.   Why  is  this? 

.#.  It  is  owing  to  the  peculiar  vascularity  and  irrita- 
bility of  the  reticular  texture  of  the  face,  and  the  danger 
proceeds  from  the  cerebral  symptoms  which  cephalic  ery- 
sipelas induces. 

Q.  What  do  you  call  erysipelas  of  the  trunk  ? 

•#.   It  is  the  herpes  zoster,  the  shingles, 


i 


DERMOIT)    SYSTEM,  307 

What  are  the  terminations  of  erysipelas? 
The  mildest  termination  is  in  desquamation;  it  ends 
in  phlyctenae,  in  oedema,   and  in  suppuration,  in  which 
case  there  is  phlegmon. 

Q.   Does  erysipelas  manifest  metastasis? 

•#.  It  shifts  from  place  to  place;  and  in  some  cases  the 
translations,  or  the  sympathetic  phenomena,  are  on  inter- 
nal organs,  as  the  brain,  and  are  usually  fatal. 

Q.  What  texture  is  the  seat  of  measles'? 

A.  That  disease  is  in  the  reticular  texture  external  to 
the  chorion. 

Q.  Where  are  the  pustules  of  small-pox  located? 

A.  In  the  chorion. 

Q.  Are  all  the  herpetic  affections  located  in  the  same 
parts  of  the  dermoid  texture? 

.#.  No;  some  affect  the  reticular  texture,  and  others 
are  deeper  seated,  and  involving  the  chorion.  Some  of 
the  herpes  are  diseases  of  the  sebaceous  follicles. 

Q.  Which  is  the  seat  of  tinea  ? 

A.  Most  of  the  forms  of  tinea  are  found  on  the  surface 
of  the  chorion;  but  the  tinea  favosa  arises  from  the  seba- 
ceous follicles. 

Q.  Whence  do  warts  originate? 

A.   From  the  chorion. 

Q.  Where  are  secondary  syphilitic  symptoms  seated? 

•fl.  In  the  vascular  reticular  texture. 

Q.  Whence  do  the  horny  excrescences  proceed? 

*A.  From  sebaceous  follicles. 

Q.  In  a  former  conversation  you  said  the  anthrax  arose 
from  a  strangulation  of  the  cellular  texture. 

Ji.  Yes;  but  there  is  another  opinion,  that  the  eschars 


306 


DERMOID    SYSTEM. 


of  anthrax  and  furuncle  proceed  from  specific  secretory 
deposition. 

Q.  What  is  the  difference  between  sympathy  of  heat 
and  sympathetic  heat? 

A.  In  sympathy  of  heat  there  is  a  delusive  impression 
that  the  skin  is  very  hot,  when  its  temperature  is  not  ele- 
vated. Sympathetic  heat  means  the  heat  of  one  organ  oc- 
casioned by  a  disease  of  another  part. 


. 


309     ) 


EPIDERMOID  SYSTEM. 


Q.  Why  is  the  epidermoid  texture  considered  sepa- 
rately from  the  dermoid  ? 

«/?.  Because  its  organization,  properties,  functions,  and 
growth,  differ  from  those  of  the  dermoid. 

Q.  What  belongs  to  the  epidermoid  tissue? 

«/?.  The  external  epidermis,  the  mucous  epidermis,  and 
the  nails. 


Of  the  External  Epidermis. 

Q.  What  passes  from  the  dermis  through  the  epider- 
mis? 

«/?.  The  exhalents  and  hairs.  The  absorbents  pass  from 
without  inward. 

Q.  What  causes  destroy  the  adhesion  of  the  cuticle  to 
the  cutis? 

Ji.  Inflammation  of  the  skin,  cutaneous  eruptions,  idio- 
pathic  fevers,  diseases  of  the  viscera,  and  violent  rubefa- 
cients. 

Q.  How  do  these  causes  act? 

t#.  By  an  alteration  of  the  vital  forces  of  the  parts,  per- 
haps of  the  dermis. 

Q.  What  is  the  organization  of  the  epidermis? 

%/?.  It  is  a  single  layer  over  the  whole  body,  except  on 
the  palms  of  the  hands  and  bottoms  of  the  feet;  no  fluid 
penetrates  it;  it  has  neither  nerves  nor  cellular  texture  5 


310  EPIDERMOIl)    SYSTEM. 

it  is  the  most  incorruptible  of  the  textures.     It  is  almost 
inorganic. 

Q.  Has  it  vital  forces  ? 

A.  It  has  none;  it  is  destitute  of  sympathies. 

Q.   How  then  would  you  describe  the  epidermis? 

•#.  As  a  semi-organized,  or  even  inorganic  body,  placed 
by  nature  between  external  inanimate  substances,  and  the 
organized  dermis,  in  order  to  assist  their  passage  and  guard 
against  their  force. 

Q.  How  does  it  differ  from  other  tissues? 

£.  In  the  property  of  reproduction;  and  from  some 
textures  it  differs  in  this,  that  whereas,  in  diseases  these 
textures  assume  animal  sensibility,  foreign  to  them  in 
health,  and  thus  feel  pain,  the  epidermoid  system  is  inca- 
pable, either  in  health  or  disease,  of  assuming  animal  sen- 
sibility. 

Q.   How  are  the  epidermoid  pores  seen? 

Jl.  Their  places  are  seen  in  those  of  the  distinct  drops 
of  sweat  on  the  skin;  the  pores  can  be  seen  if  a  piece  of 
epidermis  be  held  up  between  the  eye  and  a  strong  light, 
but  you  cannot  distinguish  the  exhalent  from  the  absorb- 
ent pores. 

Q.  What  unites  the  epidermis  to  the  cutis? 

.#.  The  exhalents,  absorbents,  and  hairs. 

Q.  Whence  arises  the  thickness  of  the  epidermoid  sys- 
tem on  the  hands  and  feet? 

*ft.  It  arises  from  numerous  epidermoid  layers,  and 
perhaps  there  is  some  unknown  difference  in  the  organi- 
zation. 


EPIDERMOID    SYSTEM.  311 


Of  the  Internal  Epidermis. 

Q.  Where  do. you  find  this? 

•#.  At  the  entrance  of  the  mouth,  of  the  anus,  of  the 
urethra,  and  of  the  nasal  fossa.  As  it  passes  along  the  mu- 
cous surfaces,  it  gradually  disappears;  in  the  stomach  it 
disappears  at  the  cardia. 

Q.  Does  it  exist  in  the  deep-seated  mucous  membranes? 

A.  It  does  not;  it  is  lost  on  them. 

Q.  What  are  the  properties  of  the  mucous  epidermis  ? 

t#.  They  are  the  same  with  those  of  the  external  epi- 
dermis. 

Q+  What  are  its  uses? 

t#.  The  same  with  those  of  the  external  epidermis,  to 
defend  the  subjacent  papillae. 


OF  THE  PILOUS  SYSTEM. 

Q.  What  is  the  organization  of  the  hairs? 

*#.  An  external  epidermis,  and  an  internal  vascular 
tissue,  which  is  the  pilous  texture. 

Q.  What  reason  have  you  for  supposing  the  internal 
texture  vascular? 

A.  Because,  in  disease,  as  the  plica  polonica,  the  hair 
bleeds. 

Q.  To  what  texture  is  the  pilous  analogous  ? 

t#.  To  the  reticular  of  the  skin,  which  has  a  colouring 
and  a  vascular  tissue. 

Q.  What  phenomena  depend  for  explanation  on  the  vas- 
cular character  of  the  internal  texture  of  the  hair? 

«#.  The  change  of  colour  of  the  hair  suddenly,  from 
fright,  grief,  &c.;  the  bleeding  of  the  plica  polonica;  the 
pain  of  the  head  from  cutting,  or  from  too  much  hair. 

Q.  What  is  the  origin  of  the  hair? 
«/?.  It  arises  from  the  sub-cutaneous  fat  or  the  cellular 
texture.     Each  hair  is  contained  in  a  small,  membranous 
canal. 

Q.  Have  the  hairs  vital  properties? 
*fl.   They  are  destitute  of  animal  sensibility,  but  organic 
forces  are  seen  in  the  diseases  of  the  hair.     They  are  said 
to  have  nerves. 


ANALYTICAL  TABLE  OF  CONTENTS. 


GENERAL  OBSERVATIONS. 

Of  the  Physiological  and  Physical  Sciences,  and  the  Properties  which  pre- 
side over  their  Phenomena. 

Of  animate  and  inanimate  beings.— Of  the  sciences  which  treat  of  their 
phenomena. — Of  vital  and  non-vital  properties.  -  9 

Characters  of  the  Vital  Properties  compared  with  those  of  the  Physical. 

Extreme  variableness  of  the  first. — Consequences  of  this  principle  as  it 
regards  their  phenomena. — There  can  only  be  diseases  where  there 
are  vital  properties. — Of  sympathies. — Properties  of  vegetable  and 
animal  life. — Phenomena  which  result  from  these  properties.  10 

Of  the  Vital  Properties  and  their  Phenomena  considered  in  relation  to  the 
Solids  and  Fluids. 

The  vital  properties  essentially  seated  in  the  solids. — These  are  the 
seat  of  most  diseases. — The  fluids  may  however  be  affected. — Ave- 
nues by  which  the  fluids  become  affected. — Division  of  the  fluids  into 
those  of  composition  and  decomposition. — Sympathetic  impressions 
conveyed  and  seated  in  the  solids.  -  13 

Of  the  Properties  Independent  of  Life. 

Properties  of  Texture. — Of  contractility  by  horny  hardening. — Of  ani- 
mal contractility. — Of  sensible  organic  contractility. — Of  contractility 
of  texture  from  want  of  extension. — Of  insensible  organic  contracti- 
lity. -  ....  15 

Of  Animal  Organization. 

Cause  upon  which  the  vital  properties  depend. — Of  the  elementary 
textures.— Division  of  the  organized  systems. — Of  the  generative  tis- 
sues.— Of  the  insulated  tissues. — Of  the  nutritive  parenchyma  and 
nutritive  matter  of  an  organ. — Of  the  first  aspect  and  of  the  progress 
of  organization. — Elective  power  of  an  organ. — Secretion — Life  of  a 
part. — Disease. — Sympathies. — Influence  of  texture  on  disease. — 
Acute  and  chronic  diseases  relative  to  the  vital  properties  of  the 
textures.  -  16 

Of  the  Functions. 

Functions  of  animal  and  organic  lives,  their  centres,  and  the  nerves 
belonging  to  each. — Beclard's  elements  of  organization. — MeckePs 
doctrine  of  organization.  -  20 

40 


314  ANALYTICAL    TABLE    OP    CONTENTS. 


OF  LIFE. 

Definition. — Division — Characteristics  of  organic  life. — Peculiarities 
of  animal  life. — Functions  of  animal  life. — Functions  of  organic 
life. 22 

Difference  between  Animal  and  Organic  Life. 

Symmetry  in  animal  life,  irregularity  in  organic  life. — Animal  life  in- 
termittent, organic  life  perpetually  active  from  birth  to  death. — 
Dreaming. — Impressions  on  animal  life  variant,  on  organic  life  uni- 
form.— Location  of  intellect  and  the  passions. — Effects  of  the  pas- 
sions on  the  organs 23 

OF  THE  PROPERTIES  OF  ANIMATED  BEINGS. 
1.    Vital  Properties. 

Sensibility  and  contractility. — Animal  and  organic  sensibility. — Effect 
of  sudden  death  on  these  two  kinds  of  sensibility. — Animal  and  or- 
ganic contractility. — Sensible  and  insensible  organic  contractility. — 
Effects  of  sudden  death  on  these  contractilities. — Connexion  of 
these  contractilities  with  their  respective  sensibilities. — Difference 
in  their  relation. — Difference  between  sensible  and  insensible  orga- 
nic contractility. — Difference  between  organic  contractility  and  or- 
ganic sensibility. — Contractility  not  the  exclusive  property  of  mus- 
cular tissue.  -  -  -  ......  27 

2.  Properties  of  Texture. 

Extensibility  and  contractility  of  tissue. — Cause  on  which  the  textural 
properties  depend. 32 

OF  ANIMAL  LIFE. 

Distinction  between  animal  and  organic  life. — Period  of  commence- 
ment of  the  two  lives. — Laws  governing  the  education  of  the  func- 
tions of  animal  life. 34 

OF  ORGANIC  LIFE. 

Organ  in  this  system  first  developed. — Difference  between  foetal  orga- 
nic and  independent  organic  life. — Perfection  of  organic  life  depends 
on  organization. — Seat  of  the  moral  character. — Animal  life  dies 
first.  ------ 36 


ON  DEATH. 

General  Observations. 37 

On  the  Influence  of  the  Death  of  the  Heart  upon  that  of  the  Brain. 
Manner  in  which  the  heart  influences  the  brain.      -        -        -         37 


ANALYTICAL    TABLE    OP    CONTENTS.  315 

On  the  Influence  of  the  Death  of  the  Heart  upon  that  of  the  Lungs. 
Functions  of  the  lungs. — Manner  in  which  the  lungs  are  affected  when 
the  red  blood  heart  is  interrupted  in  its  functions.        -         -          38 

On  the  Influence  of  the  Death  of  the  Heart  upon  that  of  the  Organs  gene- 
rally. 

Manner  in  which  death  of  the  heart  produces  death  of  the  organs  ge- 
nerally  38 

On  the  Influence  of  the  Death  of  the  Heart  on  General  Death. 
Influence  of  the  death  of  the  heart  on  the  production  of  general  death. 
On  death  from  mental  emotion. — On  syncope.     ...          39 

On  the  Influence  of  Death  of  the  Lungs  upon  that  of  the  Heart. 
Condition  of  the  lungs  in  syncope. — Death  takes  place  in  the  lungs  by 
the  cessation  of  their  mechanical  and  chemical  functions. — Manner 
in  which  these  functions  are  destroyed. — Effect  of  the  interruption 
of  the  functions  of  the  lungs  upon  the  heart. — Influence  of  the  black 
blood  upon  the  organs  generally. — State  of  the  heart  in  asphyxia.  41 

On  the  Influence  of  the  Death  of  the  Lungs  upon  that  of  the  Brain. 
Manner  in  which  death  of  the  lungs  produces  that  of  the  brain.         44 

On  the  Influence  of  the  Death  of  the  Lungs  upon  that  of  the  Organs  ge- 
nerally. 

Experiments  showing  the  progress  of  asphyxia  in  animals. — Effect  of 
black  blood. 47 

On  the  Influence  of  Death  of  the  Lungs  on  General  Death. 

Death  from  interruption  of  the  mechanical  function  of  the  lungs. — 
Death  from  interruption  of  the  chemical  functions  of  the  lungs. — 
Asphyxia  from  gases. — Modes  in  which  deleterious  gases  affect  the 
lungs. — Deleterious  vapours  absorbed  into  the  general  circulation  in 
asphyxias  operate  on  the  brain  and  nerves. — In  diseases  death  com- 
mences in  the  lungs. — Colour  of  the  arterial  blood  after  death.  48 

On  the  Influence  of  Death  of  the  Brain  upon  that  of  the  Lungs. 
Mode  in  which  death  of  the  brain  affects  the  lungs.         .         -          50 

On  the  Influence  of  Death  of  the  Brain  upon  that  oftfie  Heart. 
Mode  in  which  death  of  the  brain  affects  the  heart.  51 

On  the  Influence  of  Death  of  the  Brain  on  the  Organs  generally. 
Mode  in  which  death  of  the  brain  affects  the  organs  generally.  52 

On  the  Influence  of  Death  of  the  Brain  on  General  Death. 
Successive  phenomena  produced  on  the  body  in  general  by  death  of 
the  brain. 52 


•'*!(>  ANALYTICAL    TABLE    OP    CONTENTS. 

SYSTEMS  COMMON   TO  ALL  THE  APPARA- 
TUS. 

OF  THE  CELLULAR  SYSTEM. 

General  Remarks.    - -        -          52 

Of  the  Cellular  System  considered  in  relation  to  the  Organs, 

Of  the  Sub-cutaneous  Cellular  Texture 53 

Of  the  Sub-mucous  Cellular  Texture.         ...•_.  54 

Of  the  Sub-serous  Cellular  Texture.  55 

Of  the  Arterial  Cellular  Texture.  56 

Of  the  Venous  Cellular  Texture.  56 

Of  the  Cellular  Texture  embracing  the  Organs  on  all  Sides.  57 

Of  the  Internal  Cellular  Structure  of  the  Organs. 
Its  relation  to  the  other  organs. — Its  properties.      -        -  58 

Of  the  Cellular  System  considered  independently  of  the  other  Organs. 
Cellular  Texture  of  the  Head  and  Face.      ......          59 

Of  the  Cellular  Texture  of  the  Trunk  and  Extremities. 
Vertebral  cellular  texture. — Cervical  cellular  texture. — Pectoral  cel- 
lular texture. — Abdominal  cellular  texture. — Cellular  texture  of  the 
pelvis. — Cellular  texture  of  the  extremities.         -        -        -          60 

Of  the  Forms  of  the  Cellular  System  and  of  the  Fluids  it  contains. 
Of  the  cells. — Of  the  serum  of  the  cellular  system. — Of  the  cellular 

fat.      -         -         - 62 

Organization  of  the  Cellular  System. 
Parts  which  enter  into  its  organization. 66 

Properties  of  the  Cellular  Texture. 

1.  Textural Properties.—  Extensibility.— Contractility.     -  68 

2.  Vital  Properties. — Animal  sensibility. — Organic  sensibility.— Insen- 
sible organic  contractility. — Sensible  organic  contractility. — Sympa- 
thies.— Character  of  the  Vital  properties.     -  69 

3.  Properties  of  Reproduction. — Influence  of  the  cellular  texture  on  the 
formation   of  cicatrices. — Inflammation. — Granulations. — Suppura- 
tion.— Contraction  of  the  granulations. — Adhesion. — Union  by  the 
first  intention. — Influence  of  the  cellular  tissue  in  the  formation  of 
tumours  and  cysts. 71 

Development  of  the  Cellular  Texture. 
States  of  the  cellular  system  in  the  first  age  and  in  after  ages.  76 

PATHOLOGY  or  TIIK   CELMTLAH  Tissi  i 
Diseases  of  the  cellular  tis  __.---          77 


I 


ANALYTICAL    TABLE    OF    CONTENTS.  317 

NERVOUS  SYSTEM. 

General  Divisions. 82 

I.  NERVOUS  SYSTEM  OF  ANIMAL  LIFE. 

Centre  of  the  nervous  system  of  animal  life. — Centre  of  the  nervous 
system  of  organic  life. — Nervous  system  of  animal  life  symmetrical. — 
Relative  size  of  the  brain  and  nerves.  82 

External  Forms  of  the  Nervous  System  of  Animal  Life. 

Of  the  cerebral  nerves. — Of  the  nerves  arising-  from  the  cerebrum. — Of 
the  nerves  originating  from  the  tuber  annulare  and  its  elongations. — 
Of  the  spinal  nerves. — Of  the  decussation  of  the  nerves.— Of  the 
nervous  tunics. — Communications  of  the  nerves. — Course  and  plex- 
uses of  the  spinal  nerves. — Nervous  trunks. — Nervous  branches. — 
Nervous  anastomoses. — Systems  destitute  of  nerves.  - 

Organization  of  the  Nervous  System  of  Animal  Life. 
Nervous  filaments  and  chords. — Nature  and  origin  of  the  nervous  coat. 
Action  of  certain  substances  on  the  nervous  coat. — Medullary  sub- 
stance.— Comparison  between  the  cerebral  and  nervous  medullary 
substance. — Cellular  texture  of  the  nerves. — Blood-vessels.  87 

Properties  of  the  Nervous  System  of  Animal  Life. 

1.  Properties  of  texture,  very  slightly  marked.  90 

2.  Vital  Properties. — Animal  sensibility. — Internal  and  external  sensa- 
tions.— Influence  of  the  nerves  on  the  animal  contractility  of  other 
parts. — Organic  contractility  and  sensibility. — Influence  of  the  nerves 
on  the    organic  properties  of   other  parts. — Sympathies  of  the 
nerves. 90 

3.  Properties  of  Reproduction.  95 

Development  of  the  Nervous  System  of  Animal  Life. 
State  of  the  system  in  the  fa-tus. — In  after  life.— Pathological  states  of 
the  brain.     -        -         -        -         -        -        ....          95 

II.  NERVOUS  SYSTEM  OF  ORGANIC  LIFE. 
General  Remarks. 

Of  the  Ganglions. 

Definition. — Situation. — Form. — Organization. — Properties. — Diseases. 
Development. — Cerebral  ganglions. 

Of  the  Nerves  of  Organic  Life. 

Course. — Plexuses. — Structure. — Properties. — General  remarks.  101 
PATHOLOGY  OF  THE  NERVOUS  SYSTEMS  OF  ANIMAL  AND  ORGANIC  LIFE. 
Diseases  of  the  brain. — Diseases  of  the  nerves.  -  -  103 


318  ANALYTICAL    TABLE    OF    CONTENTS, 


VASCULAR  SYSTEM. 

I.  VASCULAR  SYSTEM  WITH  RED  BLOOD. 
General  Remarks  upon  the  Circulation. 

Division  of  the  circulation. — Circulation  of  red  blood. — Circulation  of 
black  blood. — General  mechanical  phenomena  of  the  two  circula- 
tions.— General  uses  of  the  circulation  with  red  blood. — General 
uses  of  the  circulation  with  black  blood.  -  -  -  107 

Situation,  Forms,  and  General  Arrangement  of  the  Vascular  Sys- 
tem.   110 

On  the  Organization  of  the  Vascular  System  with  Red  Blood. 

Peculiar  membrane  of  the  arteries. — Common  membrane  of  the  red 
blood. 112 

Properties  of  the  Vascular  System  with  Red  Blood. 

1.  Physical  Properties. — Elasticity.         .         -        -        -        -         114 

2.  Properties  of  Texture.  —Extensibility.— Contractility.  1 15 

3.  Vital  Properties. — Influence  of  the  heart  on  the  motion  of  the  red 
blood. — Of  the  pulse. — Sympathies. 117 

Of  the  Vascular  System  of  Red  Blood  in  different  Ages. 
State   in  the   foetus. — Sabatier's   division   of  the  foetal  circulation. — 
Changes  which  take  place  at  birth. — State  in  after  life. — General 
observations. 120 

PATHOLOGY  OF  THE  VASCULAR  SYSTEM  WITH  RED  BLOOD. 
Diseases  of  the  Arteries.  124 

II.  VASCULAR  SYSTEM  WITH  BLACK  BLOOD. 

Situation,  Forms,  Division,  and  General  Arrangement.      -        -        126 

Organization  of  the  Vascular  System  with  Black  Blood. 

Peculiar  membrane  of  the  veins. — Common  membrane  of  the  black 
blood.— Valves  of  the  veins. — Action  of  reagents  upon  the  venous 
texture. ^-Cellular  texture.— Exhalents  and  absorbents.— Nerves.  129 

Properties  of  the  Vascular  System  with  Black  Blood. 
1.  Properties  of  Texture.—  Extensibility.—  Contractility.  -         130 

•2.  Vital  Properties. — Venous  pulse. — Vital  forces  greater  in  the  veins 
than  arteries.— -Motion  of  the  black  blood. — Parallel  between  the  cir- 
culation in  the  arteries  and  veins. 131 

Development  of  the  Arterial  System  with  Black  Blood. 
State  in  foetal  life.— State  in  old  age.  -        -        133 

Of  the  Abdominal  System  with  Black  Blood. 
Venn  portal  circulation. — Properties  and  sympathies  of  the  abdominal 


ANALYTICAL    TABLE    OF    CONTENTS.  319 

venous  system. — Peculiar  membrane  of  the  hepatic  portion. — Influ- 
ence of  the  injection  of  air  into  the  veins. — Common  lining  mem- 
brane of  the  abdominal  portion. — Course  of  the  blood  through  the 
liver. — Circulation  of  the  abdominal  veins. — On  the  liver. — Blood  of 
the  vena  portarum. — Spleen. — Of  the  bile. — Development.  134 

PATHOLOGY  OF  THE  VASCULAR  SYSTEM  WITH  BLACK  BLOOD. 
Disease  of  the  veins.        --------        138 


CAPILLARY  SYSTEMS. 
Division. -         -         141 

I.  GENERAL  CAPILLARY  SYSTEM. 

Its  extent. — Its  division. — Capillaries  which  carry  red  blood. — Those 
which  convey  white  fluids. — Those  which  give  passage  to  both  red 
and  white  fluids. — Causes  upon  which  the  number  of  capillaries  in  a 
part  depend. — Active  and  passive  secretion  and  exhalation. — Defi- 
nition of  the  general  capillary  system. — Anastomoses. — Pathology 
of  haemorrhage.— Relation  of  the  general  capillary  system  to  the  ar- 
teries and  veins. — The  effect  of  this  relation  on  the  appearance  of 
parts  on  dissection. — How,  notwithstanding  the  general  communicar 
tion  of  the  capillary  system,  the  blood  and  the  fluids  differing  from 
it  remain  separate. — Irritation. — Organic  sensibility.  -  -  141 

Of  Inflammation. 145 

Of  the  Capillary  Circulation. — The  fluids. — The  motions  of  the  fluids. 
— Division  of  diseases. — Influence  of  atmospheric  changes. — Blood- 
letting.   148 

Of  the  Capillaries  considered  as  the  Seat  of  the  Production  of  Jlnimal 
Heat 150 

II.  PULMONARY  CAPILLARY  SYSTEM. 

Definition. — How  all  the  blood  of  the  general  system  can  go  through 
the  pulmonary.— Diseases  of  the  lungs. — Pulmonary  circulation  in 
diseases. — Erectile  tissue. 152 


EXHALENT  SYSTEM. 

General  remarks  on  exhalation  and  secretion,  and  exhaled  and  secreted 
fluids. 156 

General  Arrangement  of  the  Exhalents. — Division.     -        -        -        157 

Properties  and  Functions  of  the  Exhalent  System. 
Vital  properties.— Natural  exhalations.— Morbid  exhalations.  157 


320                  ANALYTICAL    TABLE    OF    CONTENT- 
ABSORBENT  SYSTEM. 
Definition. -        -        162 

Of  the  Absorbent  Vessels. 

Their  origin. — Termination. — Course  and  division. — Forms.— -Capa- 
city.— Anastomoses. — Effects  of  obstruction  of  the  absorbents — 
Structure  of  the  absorbents. 162 

Of  the  Lymphatic  Glands. 
Situation. — Colour. — Development. — Texture.       -  165 

Properties  of  the  Absorbent  System. 

1.  Properties  of  Texture. — Extensibility. — Contractility.  166 

2.  Vital  Properties. — Animal  sensibility. — Organic  sensibility. — Orga- 
nic contractility. — Character  of  the  vital  properties. — Inflammation. 
Sympathies.         -        -        -  166 

Of  Absorption. 

Influence  of  the  vital  forces  on  this  function.— Influence  of  medicines. 
— Absorption  of  morbific  matter. — Causes  which  vary  the  natural 
type  of  the  absorbents. — Absorption  at  different  ages. — Structure  of 
a  gland. — Sensible  organic  contractility.  -  -  -  -  167 

PATHOLOGY  OP  THE  ABSORBENT  SYSTEM. 
Diseases  of  the  absorbent  system -        170 


OF   SYSTEMS   PECULIAR  TO  CERTAIN  AP- 
PARATUS. 

General  Observations. -        -        172 

OSSEOUS  SYSTEM. 

Definition.      -  ........        173 

Forms  of  the  Osseous  System. 

Long  bones. — Flat  bones. — Short  bones. — Bony  eminences. — Osseous 
cavities. 173 

Of  the  Organization  of  the  Osseous  Texture. 

Texture  peculiar  to  the  osseous  system. — Texture  with  cells. — Com- 
pact texture. — Arrangement  of  the  two  osseous  textures  in  three 
kinds  of  bones. — Composition  of  the  osseous  texture.— Parts  which 
enter  into  the  organization  of  the  osseous  system.  177 

Of  the  Properties  of  the  Osseous  System. 
1,  Physical  Properties.  -        -        -        -        -      '  -        -        181 


ANALYTICAL    TABLE    OF    CONTENTS.  321 

2.  Textural  Properties.    -  ....        181 

3.  Vital  Properties. — Character  of  these  properties.        -        -        182 

Articulations  of  the  Osseous  System. 

Division  of  the  articulations. — Moveable  articulations. — Immoveable 
*      articulations. 183 

Development  of  the  Osseous  System. 

Period  at  which  the  osseous  system  is  complete. — Mucous,  cartilagi- 
nous, and  osseous  states  of  the  bones. — State  of  the  osseous  system 
after  its  growth. — Changes  which  take  place  in  old  age. —Develop- 
ment of  the  callus.— Of  the  teeth.— Of  the  sesamoid  bones.  187 

OF  THE  MEDULLARY  SYSTEM  OF  THE  BONES. 

Origin. — Properties. — Division. — Diseases  of  the  medulla. — Develop- 
ment.— Functions. — Spina  ventosa. 192 

PATHOLOGY  OF  THE  OSSEOUS  TISSUE. 
Diseases  of  the  osseous  tissue.        ...  193 

PATHOLOGY  OP  THE  MEDULLARY  SYSTEM. 
Diseases  of  the  medullary  tissue 195 


CARTILAGINOUS  SYSTEM. 

Division. — Definition.      ...        -  -        196 

Forms  of  the  Cartilaginous  System. 

Cartilages  of  the  moveable  articulations. — Those  of  the  immoveable 
bones. — Those  of  the  parietes  of  cavities.     ....        196 

Organization  of  the  Cartilaginous  System. 

Peculiar  organization  of  cartilage. — Change  effected  in  cartilage  by 
disease. — Common  organization  of  cartilage.         ...         197 

Properties  of  the  Cartilaginous  System. 

1.  Physical  Properties. — Elasticity. — Position  of  cartilages.  198 

2.  Textural  Properties. 198 

3.  Vital  Properties. — Character  of  the  vital  properties.  -        -  198 

Development  of  the  Cartilaginous  System. 
State  in  the  first  age. — State  in  after  ages. — Diseases.  -        199 


FIBROUS  SYSTEM. 

Of  the  Forms  and  Divisions  of  the  Fibrous  System. 

Of  the  fibrous  membranes.    Fibrous  capsules.  Fibrous  sheaths.  Fibrous 
aponeuroses, — Fibrous  fascia.  Tendons.  Ligaments.   -        -        201 

41 


322  ANALYTICAL    TABLE    OF    CONTENTS. 

Organization  of  the  Fibrous  System. 

Texture  of  the  fibrous  system.         -         ...  202 

Properties  of  (he  Fibrous  System. 

1.  Physical  Properties. 203 

2.  Textural  Properties.  203 

3.  Vital   Properties. — Character    of   the    vital    properties. — Sympa- 
thies.      ^ 203 

Development  of  the  Fibrous  System. 
Fibrous  system  in  early  years. 205 

Of  the  Fibrous  Membranes  in  General. 

General  Remarks. -        -         -  -        205 

Of  the  Periosteum.  - 205 

Of  the  Fibrous  Capsules. -        206 

Of  the  Fibrous  Sheaths.    -  -        207 

Of  the  Aponeuroses.  207 

Of  the  Tendons.      -        -  209 

Of  the  Ligaments.   -        -  209 
Of  the  Yellow  Elastic  Tissue,   -------        210 

PATHOLOGY  OF  THE  FIBROUS  SYSTEM. 

Diseases  of  the  fibrous  system.         -         -        -        -        -  21 


OF  THE  FIBRO-CARTILAGINOUS  SYSTEM. 


10 

• 


Organs  where  it  is  found. — Functions  of  the  tissue. — Organization. — 
Properties. — State  of  the  system  in  after  ages.     -         -         -        212 


MUSCULAR  SYSTEM. 

General  Division.     -        -  -  214 

I.  Or  THE  MUSCULAR  SYSTEM  OF  ANIMAL  LIFB. 

Characters.  -        -        -  214 

Of  the  Forms  of  the  Muscular  System  vf  Animal  Life. 

1.  Of  the  Long  Muscles.  ....  214 

2.  Of  the  Broad  Muscles.  -    '    -  215 

3.  Of  the  Short  Muscles.  216 

Organization  of  the  Muscles. 
Texture  peculiar  to  their  organization. — Fibres. — Their  composition. — 


ANALYTICAL    TABLE     OF    CONTENTS.  323 

Parts  common  to  the  organization  of  this  system. — Cellular  texture. 
—Blood-vessels.— -Nerves.  -         -        -         -         -        -        216 

Properties  of  the  Muscular  System  of  Animal  Life. 

1.  Properties  of  Texture. — Extensibility. — Contractility  of  texture.  219 

2.  Vital  Properties. — Properties  of  Animal  Life. — -Sensibility. — Animal 
contractility. — Animal  contractility  considered  in  the  brain,  in  the 
nerves,  in  the  muscles. — Causes  which  excite  animal  contractility. — 
Contractility  in  the  foetus,  and  after  death. — Difference  between  ani- 
mal contractility  and  irritability. — Parts  in  which  animal  contractility 
first  and  last  ceases. — Sensible  organic  contractility. — Sympathies. — 
Characters  of  the  vital  properties. 221 

Phenomena  of  the  Action  of  the  Muscular  System  of  Animal  Life. 
Force  of  muscular  contraction. — Rapidity  of  contraction* — Effect  of 
muscular  contraction.  ..„._.-         227" 

Development  of  the  Muscular  System  of  Animal  Life. 
State  in  the  foetus. — During-  growth. — Effect  of  disease.  -         228 

II.  OF  THE  MUSCULAR  SYSTEM  OF  ORGANIC  LIFE. 

Where  found.  -         -         -         -         229 

Forms  and  Organization  of  the  Muscular  System  of  Organic  Life. 

Forms. — Organization. 229 

Properties  of  the  Muscular  System  of  Organic  Life. 

1.  Properties  of  Texture.—  Extensibility.— Contractility.  230 

2.  Vital  Properties. — Animal  sensibility. — Animal   contractility. — Or- 
ganic properties. — Sensible  organic  contractility. — Effect  of  stimuli, 
age,  temperament,  and  death,  on  this  property. — Sympathies. — Cha- 
racter of  the  vital  properties.       231 

Phenomena  of  the  action  of  the  Muscular  System  of  Organic  Life. 
Force  of  contraction. — Dilatation.  -  235 

Development  of  the  Muscular  System  of  Organic  Life. 

Causet  which  set  the  muscles   of  organic  life  into  activity. — Their 
growth. — Controlling  power  of  the  will  over  the  organic  muscles.  236 

PiTTTOLOGY    OF    THE    MUSCULAR    TlSSUE. 

Diseases  of  the  muscular  tissue  of  animal  and  of  organic  life.   -         237 


MUCOUS  SYSTEM. 

Whence  it  derives  its  name. -         239 

Of  the  Divisions  and  Forms  of  the  Mucous  System. 

Forms.—  Gastro-pulmonary  and  gastro-urinary  mucous  membranes. — 
Pathological  considerations. — Surfaces.         -         -  -         239 


324  ANALYTICAL    TABLE    OF    CONTENTS. 

*  ' 

Organization  of  the  Mucous  System. 

Mucous  chorion. — Mucous  papillae. — Mucous  glands  and  the  fluids  they 
secrete. — Blood-vessels. — Exhalents. — Absorbents. — Nerves.  241 

Properties  of  the  Mucous  System. 

1.  Properties  of  Texture. — Extensibility. — Contractility.          -        245 

2.  Vital  Properties. — Animal  sensibility. — Properties  of  organic  life.— 
Sympathies. — Characters  of  the  vital  properties.  -        245 

Development  of  the  Mucous  System. 

State  at  birth.— After  ages.— Structure  of  the  papillae.— Mucous  folli- 
cles.— Alveolar  structure, — Membrane  lining  abscesses  and  fis- 
tulae. 250 

PATHOLOGY  OF  THE  Mucous  TISSUE. 
Diseases  of  the  mucous  tissues.       -        -        -        -        -        -        252 


SEROUS  SYSTEM. 

Why  so  called.  -        -        -        257 

Of  the  Extent,  Forms,  and  Fluids  of  the  Serous  System. 
Principal    mucous    membranes. — Their    forms. — Extent. — Fluids. — 
Form  of  each  serous  membrane. — Free  surface. — Adhering  surface. 
Doctrine  of  organic  life. — Disease. — Serous  fluids.        -        -        257 

Organization  of  the  Serous  System. 

Characters  of  the  organization  of  the  serous  tissue. — Nature  of  this 
membrane. — Exhalents. — Absorbents. — Blood-vessels. — Pathologi- 
cal phenomena. .  259 

Properties  of  the  Serous  System. 

1.  Properties  of  Texture. — Extensibility.— Contractility.  -         261 

2.  Vital  Properties. — Sympathies. 262 

Development  of  the  Serous  System.  * 

Progress  of  development.— Alterations  produced  in  the  serous  system 
by  disease.  -  -  -  263 

PATHOLOGY  OF  THE  SEROUS  TISSUE. 
Diseases  of  the  serous  system. 264 


SYNOVIAL  SYSTEM. 

Points  of  resemblance  and  difference  between  the  synovial  and  serous 
systems. — Division  of  the  synovial  system.   -  270 


ANALYTICAL    TABLE    OF    CONTENTS.  325 

1.  Of  the  Articular  Synovial  System. 

Manner  in  which  the  synovia  is  formed. — Appearance  of  the  synovia. — 
Form  of  the  synovial  membrane. — Properties  of  the  synovial  tissue. 
— Sympathies. — Development. 270 

2.  Synovial  System  of  the  Tendons. 

Where  found. — Organization,  properties,  functions,  and  sympathies. — 
Synovial  fringes.  ..-..--.  272 


GLANDULAR  SYSTEM. 

General  Observations. -        -        -        274 

Situation,  Forms,  Division,  &?c.  of  the  Glandular  System. 
Position  of  the  glands. — Excretion. — Division. — Forms.  -        -        274 

Organization  of  the  Glandular  System. 

Peculiar    texture. — Forms. — Excretory    ducts. — Cellular    texture. — 
Blood-vessels.— Blood.— Nerves.          -        -        -        -        -        275 

Properties  of  the  Glandular  System. 

1.  Properties  of  Texture.— Extensibility.—  Contractility.  -        279 

2.  Vital  Properties. — Properties  of  animal  life. — Properties  of  organic 
life. — Sympathies. — Characters  of  the  vital  properties.         -        279 

Development  of  the  Glandular  System. 
State  in  the  fetus. — During  growth. — After  growth. — In  old  age.  283 

PATHOLOGY  OF  THE  GLANDULAR  STSTBM. 
Diseases  of  the  glands 284 


DERMOID  SYSTEM. 

Uses  of  this  texture. ,                --.....  288 

Forms  of  the  Dermoid  System. 

Wrinkles. — Connexion  of  the  skin  with  the  subjacent  parts    -  288 
Organization  of  the  Dermoid  System. 

1.  Texture  peculiar  to  the  Organization.           -        -        -        -  289 

a.  Of  the  Chorion. 289 

b.  Of  the  Reticular  Texture.      -        -        -        .        .        .  290 

c.  Of  the  Papillse.     -                 -         -         -         .         .         .  292 
Action  of  Different  Bodies  m  the  Dermoid  Texture.    -        -        .  293 

2,  Parts  common  to  the  Organization  of  the  Dermoid  System.—  Cellular 


326  ANALYTICAL    TABLE    OF    CONTENTS. 

texture;  its  diseases  and  extent. — Absorbents. — Exhalents. — Exha- 
led fluid '295 

Properties  of  the  Dermoid  System. 

1.  Properties  of  Texture. — Extensibility. — Contractility.  -        -        298 

2.  Vital  Properties. — Animal  sensibility. — Parts  governed  by  animal 
sensibility,  and  those  which  belong1  to  organic  life. — Disease. — Sym- 
pathies.— Characters  of  the  vital  properties.        -  299 

Development  of  the  Dermoid  System. 

State  in  the  foetus. — During  growth. — In  old  age. — Oily  matter  of  the 
skin. — Morbid  structures. 304 

PATHOLOGY  OF  THE  DERMOID  TEXTURE. 
Diseases  of  the  skin 305 


EPIDERMOID  SYSTEM. 

General  Remarks. 309 

Of  the  External  Epidermis. 

Forms. — Organization. — No  vital  forces. — Definition. — Difference  from 
other  tissues. — Pores. — Connexion  with  the  cutis.         -        -        310 


Where  found. 
PronerHfts  and  uses. 

Of  the  Internal  Epidermis. 
Mucous  Epidermis. 

311 
311 

OF  THE  PILOUS  SYSTEM. 
Organization.     Properties 


ERRATA. 


Page  19,  line  17,  for  and  have,  read  and  their  diseases  have. 

20,  "    14,  for  The  senses,  read  Those  of  the  senses. 

22,  "    15,  for  receptions,  read  reception. 

26,  tc    19,  for  is,  read  be. 

29,  "    20,  for  larger,  read  longer. 

31,  "    15,  for  r/e*  *o  be,  read  fo  6e. 

33,  "    25,  for  faculty  -which,  read  faculty  by  -which. 

41,  "    14,  for  its,  read  their. 

44,  '     last,  for  seated  in,  read/rom. 

47,  «     28,  for  that  of,  read  z's  Ma*  of. 

48,  1 ,  for  brain,  read  lungs. 

49,  9,  for  effluvia,  read  effluvia. 
49,         23,  forjorced,  read  inspired. 

100,         30,  for  viscera,  read  organs. 

105,  5,  for  wfen,  read  where. 

107,         22,  for  on,  read  m. 

113,         27,  for  Mz's  d£#er,  read  ^  fe'nwj^  membrane  differ. 

134,         25,  for  ventricles,  read  ventricle. 

142,         18,  for  of  healthy  serous,  read  of  serous. 

145,         29,  for  irritation,  read  invitation. 

277,  «    28,  for  tearf,  read 


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